diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/README.md b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/README.md
new file mode 100644
index 00000000..aa3e5e0d
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/README.md
@@ -0,0 +1,15 @@
+# Fixing the Entry Point 1
+
+Access the directory `drills/tasks/entry-fix-1/support/`.
+We want to track issues with defining the `main()` function.
+
+Go to the subdirectory `a-c/`.
+Run the `make` command, interpret the encountered error, and resolve it by editing the `hello.c` file.
+
+Go to the subdirectory `b-asm/`.
+Run the `make` command, interpret the encountered error, and resolve it by editing the `hello.asm` file.
+
+**Bonus**: In the subdirectories `c-extra-nolibc/` and `d-extra-libc/`, find solutions that do not modify the source code of `hello.c`.
+These solutions instead modify the build system to use a different function, other than `main()`, as the program's entry point.
+
+If you're having difficulties solving this exercise, go through [this](../../../reading/README.md) reading material.
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/a-c/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/a-c/.gitignore
new file mode 100644
index 00000000..e92569d0
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/a-c/.gitignore
@@ -0,0 +1 @@
+/hello
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/a-c/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/a-c/Makefile
new file mode 120000
index 00000000..19ab98b2
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/a-c/Makefile
@@ -0,0 +1 @@
+../../support/a-c/Makefile
\ No newline at end of file
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/a-c/hello.c b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/a-c/hello.c
new file mode 100644
index 00000000..7a4ba956
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/a-c/hello.c
@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+
+static void hi(void)
+{
+	puts("Hi!");
+}
+
+static void bye(void)
+{
+	puts("Bye!");
+}
+
+int main(void)
+{
+	hi();
+	bye();
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/b-asm/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/b-asm/.gitignore
new file mode 100644
index 00000000..e92569d0
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/b-asm/.gitignore
@@ -0,0 +1 @@
+/hello
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/b-asm/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/b-asm/Makefile
new file mode 120000
index 00000000..072e0b96
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/b-asm/Makefile
@@ -0,0 +1 @@
+../../support/b-asm/Makefile
\ No newline at end of file
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/b-asm/hello.asm b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/b-asm/hello.asm
new file mode 100644
index 00000000..43bf35ca
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/b-asm/hello.asm
@@ -0,0 +1,41 @@
+; SPDX-License-Identifier: BSD-3-Clause
+
+extern puts
+extern main
+
+section .rodata
+
+    hi_str db "Hi!", 0
+    bye_str db "Bye!", 0
+
+section .text
+
+hi:
+    push ebp
+    mov ebp, esp
+
+    push hi_str
+    call puts
+
+    leave
+    ret
+
+bye:
+    push ebp
+    mov ebp, esp
+
+    push bye_str
+    call puts
+
+    leave
+    ret
+
+main:
+    push ebp
+    mov ebp, esp
+
+    call hi
+    call bye
+
+    leave
+    ret
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/c-extra-nolibc/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/c-extra-nolibc/.gitignore
new file mode 100644
index 00000000..e92569d0
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/c-extra-nolibc/.gitignore
@@ -0,0 +1 @@
+/hello
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/c-extra-nolibc/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/c-extra-nolibc/Makefile
new file mode 100644
index 00000000..e58b4d63
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/c-extra-nolibc/Makefile
@@ -0,0 +1,25 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -nostdlib -nostdinc -no-pie -m32
+AS = nasm
+ASFLAGS = -f elf32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: hello
+
+hello: hello.o start.o puts.o
+	$(CC) $(LDFLAGS) -o $@ $^
+
+hello.o: hello.c
+
+start.o: start.asm
+	$(AS) $(ASFLAGS) -o $@ $<
+
+puts.o: puts.asm
+	$(AS) $(ASFLAGS) -o $@ $<
+
+clean:
+	-rm -f hello hello.o start.o puts.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/c-extra-nolibc/hello.c b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/c-extra-nolibc/hello.c
new file mode 100644
index 00000000..9a5e1355
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/c-extra-nolibc/hello.c
@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+
+static void hi(void)
+{
+	puts("Hi!\n");
+}
+
+static void bye(void)
+{
+	puts("Bye!\n");
+}
+
+int my_main(void)
+{
+	hi();
+	bye();
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/c-extra-nolibc/puts.asm b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/c-extra-nolibc/puts.asm
new file mode 100644
index 00000000..57a09ded
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/c-extra-nolibc/puts.asm
@@ -0,0 +1,51 @@
+; SPDX-License-Identifier: BSD-3-Clause
+
+section .text
+
+global puts
+
+; /usr/include/x86_64-linux-gnu/asm/unistd_32.h
+__NR_write equ 4
+
+; Argument is message to be printed to standard output.
+puts:
+    push ebp
+    mov ebp, esp
+
+    ; Call __NR_write(1, message, message_len) (system call).
+    ;
+    ; Use x86 Linux system call convention.
+    ; https://en.wikibooks.org/wiki/X86_Assembly/Interfacing_with_Linux#Making_a_system_call
+    ;
+    ; eax stores the system call id.
+    ; ebx stores the first system call argument: 1 (standard output).
+    ; ecx stores the second system call argument: message.
+    ; edc stores the third system call argument: message length.
+
+    ; Store the write system call id in eax.
+    mov eax, __NR_write
+
+    ; Store standard output file descriptor (1) in ebx.
+    mov ebx, 1
+
+    ; Store function argument (message) in ecx.
+    mov ecx, [ebp + 8]
+
+    ; Compute message length in edx.
+    ; Find NUL byte address of message using edi. Start from message address (ecx).
+    ; Then edx <- edi - ecx.
+    mov edi, ecx
+    dec edi
+again:
+    inc edi
+    cmp byte [edi], 0
+    jne again
+
+    mov edx, edi
+    sub edx, ecx
+
+    ; Do system call.
+    int 0x80
+
+    leave
+    ret
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/c-extra-nolibc/start.asm b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/c-extra-nolibc/start.asm
new file mode 100644
index 00000000..51a69879
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/c-extra-nolibc/start.asm
@@ -0,0 +1,30 @@
+; SPDX-License-Identifier: BSD-3-Clause
+
+extern my_main
+
+section .text
+
+; /usr/include/x86_64-linux-gnu/asm/unistd_32.h
+__NR_exit equ 1
+
+global _start
+
+_start:
+    call my_main
+
+    ; Call __NR_exit(main_return_value) (system call).
+    ;
+    ; Use x86 Linux system call convention.
+    ; https://en.wikibooks.org/wiki/X86_Assembly/Interfacing_with_Linux#Making_a_system_call
+    ;
+    ; ebx stores the first system call argument.
+    ; eax stores the system call id.
+
+    ; eax is main return value. Store it in ebx.
+    mov ebx, eax
+
+    ; Store the exit system call id in rax.
+    mov eax, __NR_exit
+
+    ; Do system call.
+    int 0x80
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/d-extra-libc/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/d-extra-libc/.gitignore
new file mode 100644
index 00000000..e92569d0
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/d-extra-libc/.gitignore
@@ -0,0 +1 @@
+/hello
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/d-extra-libc/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/d-extra-libc/Makefile
new file mode 100644
index 00000000..f88b8414
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/d-extra-libc/Makefile
@@ -0,0 +1,22 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -no-pie -m32
+AS = nasm
+ASFLAGS = -f elf32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: hello
+
+hello: hello.o start.o
+	ld -static -m elf_i386 -L/usr/lib/gcc/x86_64-linux-gnu/7/32/ -o $@ $^ /usr/lib32/crti.o --start-group -lc -lgcc -lgcc_eh --end-group /usr/lib32/crtn.o
+
+hello.o: hello.c
+
+start.o: start.asm
+	$(AS) $(ASFLAGS) -o $@ $<
+
+clean:
+	-rm -f hello hello.o start.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/d-extra-libc/hello.c b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/d-extra-libc/hello.c
new file mode 100644
index 00000000..cd6af284
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/d-extra-libc/hello.c
@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+
+static void hi(void)
+{
+	puts("Hi!");
+}
+
+static void bye(void)
+{
+	puts("Bye!");
+}
+
+int my_main(void)
+{
+	hi();
+	bye();
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/d-extra-libc/start.asm b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/d-extra-libc/start.asm
new file mode 100644
index 00000000..d600983a
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/solution/d-extra-libc/start.asm
@@ -0,0 +1,36 @@
+; SPDX-License-Identifier: BSD-3-Clause
+
+extern __libc_csu_init
+extern __libc_csu_fini
+extern __libc_start_main
+extern my_main
+
+section .text
+
+global _start
+global _dl_relocate_static_pie
+
+; Adapted from GNU Libc i386 start.S
+;   https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/i386/start.S;hb=HEAD
+_start:
+    ; Align stack.
+    xor ebp, ebp
+    pop esi
+    mov ecx, esp
+    and esp, 0xfffffff0
+
+    push eax
+    push esp
+    push edx
+
+    push __libc_csu_fini
+    push __libc_csu_init
+    push ecx
+    push esi
+    push my_main
+    call __libc_start_main
+
+    hlt
+
+_dl_relocate_static_pie:
+    repz ret
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/a-c/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/a-c/.gitignore
new file mode 100644
index 00000000..e92569d0
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/a-c/.gitignore
@@ -0,0 +1 @@
+/hello
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/a-c/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/a-c/Makefile
new file mode 100644
index 00000000..cbd19a80
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/a-c/Makefile
@@ -0,0 +1,17 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -no-pie -m32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: hello
+
+hello: hello.o
+	$(CC) $(LDFLAGS) -o $@ $^
+
+hello.o: hello.c
+
+clean:
+	-rm -f hello hello.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/a-c/hello.c b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/a-c/hello.c
new file mode 100644
index 00000000..cd6af284
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/a-c/hello.c
@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+
+static void hi(void)
+{
+	puts("Hi!");
+}
+
+static void bye(void)
+{
+	puts("Bye!");
+}
+
+int my_main(void)
+{
+	hi();
+	bye();
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/b-asm/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/b-asm/.gitignore
new file mode 100644
index 00000000..e92569d0
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/b-asm/.gitignore
@@ -0,0 +1 @@
+/hello
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/b-asm/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/b-asm/Makefile
new file mode 100644
index 00000000..4985d238
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/b-asm/Makefile
@@ -0,0 +1,20 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -no-pie -m32
+AS = nasm
+ASFLAGS = -f elf32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: hello
+
+hello: hello.o
+	$(CC) $(LDFLAGS) -o $@ $^
+
+hello.o: hello.asm
+	$(AS) $(ASFLAGS) -o $@ $<
+
+clean:
+	-rm -f hello hello.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/b-asm/hello.asm b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/b-asm/hello.asm
new file mode 100644
index 00000000..aef141c3
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/b-asm/hello.asm
@@ -0,0 +1,40 @@
+; SPDX-License-Identifier: BSD-3-Clause
+
+extern puts
+
+section .rodata
+
+    hi_str db "Hi!", 0
+    bye_str db "Bye!", 0
+
+section .text
+
+hi:
+    push ebp
+    mov ebp, esp
+
+    push hi_str
+    call puts
+
+    leave
+    ret
+
+bye:
+    push ebp
+    mov ebp, esp
+
+    push bye_str
+    call puts
+
+    leave
+    ret
+
+main:
+    push ebp
+    mov ebp, esp
+
+    call hi
+    call bye
+
+    leave
+    ret
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/c-extra-nolibc/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/c-extra-nolibc/.gitignore
new file mode 100644
index 00000000..e92569d0
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/c-extra-nolibc/.gitignore
@@ -0,0 +1 @@
+/hello
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/c-extra-nolibc/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/c-extra-nolibc/Makefile
new file mode 100644
index 00000000..e58b4d63
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/c-extra-nolibc/Makefile
@@ -0,0 +1,25 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -nostdlib -nostdinc -no-pie -m32
+AS = nasm
+ASFLAGS = -f elf32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: hello
+
+hello: hello.o start.o puts.o
+	$(CC) $(LDFLAGS) -o $@ $^
+
+hello.o: hello.c
+
+start.o: start.asm
+	$(AS) $(ASFLAGS) -o $@ $<
+
+puts.o: puts.asm
+	$(AS) $(ASFLAGS) -o $@ $<
+
+clean:
+	-rm -f hello hello.o start.o puts.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/c-extra-nolibc/hello.c b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/c-extra-nolibc/hello.c
new file mode 100644
index 00000000..9a5e1355
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/c-extra-nolibc/hello.c
@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+
+static void hi(void)
+{
+	puts("Hi!\n");
+}
+
+static void bye(void)
+{
+	puts("Bye!\n");
+}
+
+int my_main(void)
+{
+	hi();
+	bye();
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/c-extra-nolibc/puts.asm b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/c-extra-nolibc/puts.asm
new file mode 100644
index 00000000..57a09ded
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/c-extra-nolibc/puts.asm
@@ -0,0 +1,51 @@
+; SPDX-License-Identifier: BSD-3-Clause
+
+section .text
+
+global puts
+
+; /usr/include/x86_64-linux-gnu/asm/unistd_32.h
+__NR_write equ 4
+
+; Argument is message to be printed to standard output.
+puts:
+    push ebp
+    mov ebp, esp
+
+    ; Call __NR_write(1, message, message_len) (system call).
+    ;
+    ; Use x86 Linux system call convention.
+    ; https://en.wikibooks.org/wiki/X86_Assembly/Interfacing_with_Linux#Making_a_system_call
+    ;
+    ; eax stores the system call id.
+    ; ebx stores the first system call argument: 1 (standard output).
+    ; ecx stores the second system call argument: message.
+    ; edc stores the third system call argument: message length.
+
+    ; Store the write system call id in eax.
+    mov eax, __NR_write
+
+    ; Store standard output file descriptor (1) in ebx.
+    mov ebx, 1
+
+    ; Store function argument (message) in ecx.
+    mov ecx, [ebp + 8]
+
+    ; Compute message length in edx.
+    ; Find NUL byte address of message using edi. Start from message address (ecx).
+    ; Then edx <- edi - ecx.
+    mov edi, ecx
+    dec edi
+again:
+    inc edi
+    cmp byte [edi], 0
+    jne again
+
+    mov edx, edi
+    sub edx, ecx
+
+    ; Do system call.
+    int 0x80
+
+    leave
+    ret
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/c-extra-nolibc/start.asm b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/c-extra-nolibc/start.asm
new file mode 100644
index 00000000..51a69879
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/c-extra-nolibc/start.asm
@@ -0,0 +1,30 @@
+; SPDX-License-Identifier: BSD-3-Clause
+
+extern my_main
+
+section .text
+
+; /usr/include/x86_64-linux-gnu/asm/unistd_32.h
+__NR_exit equ 1
+
+global _start
+
+_start:
+    call my_main
+
+    ; Call __NR_exit(main_return_value) (system call).
+    ;
+    ; Use x86 Linux system call convention.
+    ; https://en.wikibooks.org/wiki/X86_Assembly/Interfacing_with_Linux#Making_a_system_call
+    ;
+    ; ebx stores the first system call argument.
+    ; eax stores the system call id.
+
+    ; eax is main return value. Store it in ebx.
+    mov ebx, eax
+
+    ; Store the exit system call id in rax.
+    mov eax, __NR_exit
+
+    ; Do system call.
+    int 0x80
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/d-extra-libc/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/d-extra-libc/.gitignore
new file mode 100644
index 00000000..e92569d0
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/d-extra-libc/.gitignore
@@ -0,0 +1 @@
+/hello
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/d-extra-libc/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/d-extra-libc/Makefile
new file mode 100644
index 00000000..f88b8414
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/d-extra-libc/Makefile
@@ -0,0 +1,22 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -no-pie -m32
+AS = nasm
+ASFLAGS = -f elf32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: hello
+
+hello: hello.o start.o
+	ld -static -m elf_i386 -L/usr/lib/gcc/x86_64-linux-gnu/7/32/ -o $@ $^ /usr/lib32/crti.o --start-group -lc -lgcc -lgcc_eh --end-group /usr/lib32/crtn.o
+
+hello.o: hello.c
+
+start.o: start.asm
+	$(AS) $(ASFLAGS) -o $@ $<
+
+clean:
+	-rm -f hello hello.o start.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/d-extra-libc/hello.c b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/d-extra-libc/hello.c
new file mode 100644
index 00000000..cd6af284
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/d-extra-libc/hello.c
@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+
+static void hi(void)
+{
+	puts("Hi!");
+}
+
+static void bye(void)
+{
+	puts("Bye!");
+}
+
+int my_main(void)
+{
+	hi();
+	bye();
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/d-extra-libc/start.asm b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/d-extra-libc/start.asm
new file mode 100644
index 00000000..d600983a
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-1/support/d-extra-libc/start.asm
@@ -0,0 +1,36 @@
+; SPDX-License-Identifier: BSD-3-Clause
+
+extern __libc_csu_init
+extern __libc_csu_fini
+extern __libc_start_main
+extern my_main
+
+section .text
+
+global _start
+global _dl_relocate_static_pie
+
+; Adapted from GNU Libc i386 start.S
+;   https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/i386/start.S;hb=HEAD
+_start:
+    ; Align stack.
+    xor ebp, ebp
+    pop esi
+    mov ecx, esp
+    and esp, 0xfffffff0
+
+    push eax
+    push esp
+    push edx
+
+    push __libc_csu_fini
+    push __libc_csu_init
+    push ecx
+    push esi
+    push my_main
+    call __libc_start_main
+
+    hlt
+
+_dl_relocate_static_pie:
+    repz ret
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-2/README.md b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-2/README.md
new file mode 100644
index 00000000..6f71cad8
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-2/README.md
@@ -0,0 +1,6 @@
+# Fixing the Entry Point
+
+Access the directory `drills/tasks/entry-fix-2/support/`.
+Run the `make` command, interpret the encountered error, and resolve it by editing the `hello.c` file.
+
+If you're having difficulties solving this exercise, go through [this](../../../reading/README.md) reading material.
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-2/solution/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-2/solution/.gitignore
new file mode 100644
index 00000000..e92569d0
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-2/solution/.gitignore
@@ -0,0 +1 @@
+/hello
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-2/solution/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-2/solution/Makefile
new file mode 120000
index 00000000..a39be4f2
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-2/solution/Makefile
@@ -0,0 +1 @@
+../support/Makefile
\ No newline at end of file
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-2/solution/hello.c b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-2/solution/hello.c
new file mode 100644
index 00000000..7a4ba956
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-2/solution/hello.c
@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+
+static void hi(void)
+{
+	puts("Hi!");
+}
+
+static void bye(void)
+{
+	puts("Bye!");
+}
+
+int main(void)
+{
+	hi();
+	bye();
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-2/support/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-2/support/.gitignore
new file mode 100644
index 00000000..e92569d0
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-2/support/.gitignore
@@ -0,0 +1 @@
+/hello
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-2/support/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-2/support/Makefile
new file mode 100644
index 00000000..cbd19a80
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-2/support/Makefile
@@ -0,0 +1,17 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -no-pie -m32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: hello
+
+hello: hello.o
+	$(CC) $(LDFLAGS) -o $@ $^
+
+hello.o: hello.c
+
+clean:
+	-rm -f hello hello.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-2/support/hello.c b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-2/support/hello.c
new file mode 100644
index 00000000..9a410091
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/entry-fix-2/support/hello.c
@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+
+static void hi(void)
+{
+	puts("Hi!");
+}
+
+static void bye(void)
+{
+	puts("Bye!");
+}
+
+static int main(void)
+{
+	hi();
+	bye();
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/README.md b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/README.md
new file mode 100644
index 00000000..e6d2659c
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/README.md
@@ -0,0 +1,7 @@
+# Fixing Export Issues
+
+Access the directory `drills/tasks/export-fix/support/`.
+Each subdirectory (`a-func/`, `b-var/`, `c-var-2/`) contains a problem related to the export of symbols (functions or variables).
+In each subdirectory, run the `make` command, identify the issue, and edit the necessary files to resolve it.
+
+If you're having difficulties solving this exercise, go through [this](../../../reading/README.md) reading material.
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/a-func/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/a-func/.gitignore
new file mode 100644
index 00000000..95811e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/a-func/.gitignore
@@ -0,0 +1 @@
+/main
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/a-func/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/a-func/Makefile
new file mode 120000
index 00000000..9da39e10
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/a-func/Makefile
@@ -0,0 +1 @@
+../../support/a-func/Makefile
\ No newline at end of file
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/a-func/hidden.c b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/a-func/hidden.c
new file mode 100644
index 00000000..cb83f459
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/a-func/hidden.c
@@ -0,0 +1,20 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include "ops.h"
+
+int hidden_value;
+
+void init(void)
+{
+	hidden_value = 0;
+}
+
+void set(int value)
+{
+	hidden_value = value;
+}
+
+int get(void)
+{
+	return hidden_value;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/a-func/main.c b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/a-func/main.c
new file mode 100644
index 00000000..ac72986f
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/a-func/main.c
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+#include "ops.h"
+
+int main(void)
+{
+	set(10);
+	printf("get(): %d\n", get());
+
+	age = 33;
+	print_age();
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/a-func/ops.h b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/a-func/ops.h
new file mode 100644
index 00000000..22d3d3ac
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/a-func/ops.h
@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef OPS_H_
+#define OPS_H_		1
+
+void init(void);
+void set(int value);
+int get(void);
+
+extern int age;
+void print_age(void);
+
+#endif
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/a-func/plain.c b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/a-func/plain.c
new file mode 100644
index 00000000..b620ed57
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/a-func/plain.c
@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+
+int age;
+
+void print_age(void)
+{
+	printf("age: %d\n", age);
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/b-var/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/b-var/.gitignore
new file mode 100644
index 00000000..95811e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/b-var/.gitignore
@@ -0,0 +1 @@
+/main
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/b-var/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/b-var/Makefile
new file mode 120000
index 00000000..32ae761d
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/b-var/Makefile
@@ -0,0 +1 @@
+../../support/b-var/Makefile
\ No newline at end of file
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/b-var/hidden.c b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/b-var/hidden.c
new file mode 100644
index 00000000..5f8b1ec5
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/b-var/hidden.c
@@ -0,0 +1,20 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include "ops.h"
+
+static int hidden_value;
+
+void init(void)
+{
+	hidden_value = 0;
+}
+
+void set(int value)
+{
+	hidden_value = value;
+}
+
+int get(void)
+{
+	return hidden_value;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/b-var/main.c b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/b-var/main.c
new file mode 100644
index 00000000..ac72986f
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/b-var/main.c
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+#include "ops.h"
+
+int main(void)
+{
+	set(10);
+	printf("get(): %d\n", get());
+
+	age = 33;
+	print_age();
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/b-var/ops.h b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/b-var/ops.h
new file mode 100644
index 00000000..22d3d3ac
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/b-var/ops.h
@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef OPS_H_
+#define OPS_H_		1
+
+void init(void);
+void set(int value);
+int get(void);
+
+extern int age;
+void print_age(void);
+
+#endif
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/b-var/plain.c b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/b-var/plain.c
new file mode 100644
index 00000000..b620ed57
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/b-var/plain.c
@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+
+int age;
+
+void print_age(void)
+{
+	printf("age: %d\n", age);
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/c-var-2/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/c-var-2/.gitignore
new file mode 100644
index 00000000..95811e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/c-var-2/.gitignore
@@ -0,0 +1 @@
+/main
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/c-var-2/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/c-var-2/Makefile
new file mode 120000
index 00000000..0f2e757a
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/c-var-2/Makefile
@@ -0,0 +1 @@
+../../support/c-var-2/Makefile
\ No newline at end of file
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/c-var-2/hidden.c b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/c-var-2/hidden.c
new file mode 100644
index 00000000..cb83f459
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/c-var-2/hidden.c
@@ -0,0 +1,20 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include "ops.h"
+
+int hidden_value;
+
+void init(void)
+{
+	hidden_value = 0;
+}
+
+void set(int value)
+{
+	hidden_value = value;
+}
+
+int get(void)
+{
+	return hidden_value;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/c-var-2/main.c b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/c-var-2/main.c
new file mode 100644
index 00000000..ac72986f
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/c-var-2/main.c
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+#include "ops.h"
+
+int main(void)
+{
+	set(10);
+	printf("get(): %d\n", get());
+
+	age = 33;
+	print_age();
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/c-var-2/ops.h b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/c-var-2/ops.h
new file mode 100644
index 00000000..22d3d3ac
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/c-var-2/ops.h
@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef OPS_H_
+#define OPS_H_		1
+
+void init(void);
+void set(int value);
+int get(void);
+
+extern int age;
+void print_age(void);
+
+#endif
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/c-var-2/plain.c b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/c-var-2/plain.c
new file mode 100644
index 00000000..b620ed57
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/solution/c-var-2/plain.c
@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+
+int age;
+
+void print_age(void)
+{
+	printf("age: %d\n", age);
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/a-func/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/a-func/.gitignore
new file mode 100644
index 00000000..95811e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/a-func/.gitignore
@@ -0,0 +1 @@
+/main
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/a-func/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/a-func/Makefile
new file mode 100644
index 00000000..5ed84dd5
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/a-func/Makefile
@@ -0,0 +1,21 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -no-pie -m32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: main
+
+main: main.o hidden.o plain.o
+	$(CC) $(LDFLAGS) -o $@ $^
+
+main.o: main.c ops.h
+
+hidden.o: hidden.c
+
+plain.o: plain.c
+
+clean:
+	-rm -f main main.o hidden.o plain.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/a-func/hidden.c b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/a-func/hidden.c
new file mode 100644
index 00000000..a864c611
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/a-func/hidden.c
@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int hidden_value;
+
+void init(void)
+{
+	hidden_value = 0;
+}
+
+static void set(int value)
+{
+	hidden_value = value;
+}
+
+int get(void)
+{
+	return hidden_value;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/a-func/main.c b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/a-func/main.c
new file mode 100644
index 00000000..ac72986f
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/a-func/main.c
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+#include "ops.h"
+
+int main(void)
+{
+	set(10);
+	printf("get(): %d\n", get());
+
+	age = 33;
+	print_age();
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/a-func/ops.h b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/a-func/ops.h
new file mode 100644
index 00000000..22d3d3ac
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/a-func/ops.h
@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef OPS_H_
+#define OPS_H_		1
+
+void init(void);
+void set(int value);
+int get(void);
+
+extern int age;
+void print_age(void);
+
+#endif
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/a-func/plain.c b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/a-func/plain.c
new file mode 100644
index 00000000..b620ed57
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/a-func/plain.c
@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+
+int age;
+
+void print_age(void)
+{
+	printf("age: %d\n", age);
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/b-var/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/b-var/.gitignore
new file mode 100644
index 00000000..95811e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/b-var/.gitignore
@@ -0,0 +1 @@
+/main
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/b-var/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/b-var/Makefile
new file mode 100644
index 00000000..5ed84dd5
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/b-var/Makefile
@@ -0,0 +1,21 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -no-pie -m32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: main
+
+main: main.o hidden.o plain.o
+	$(CC) $(LDFLAGS) -o $@ $^
+
+main.o: main.c ops.h
+
+hidden.o: hidden.c
+
+plain.o: plain.c
+
+clean:
+	-rm -f main main.o hidden.o plain.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/b-var/hidden.c b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/b-var/hidden.c
new file mode 100644
index 00000000..a1e11369
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/b-var/hidden.c
@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+static int hidden_value;
+
+void init(void)
+{
+	hidden_value = 0;
+}
+
+void set(int value)
+{
+	hidden_value = value;
+}
+
+int get(void)
+{
+	return hidden_value;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/b-var/main.c b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/b-var/main.c
new file mode 100644
index 00000000..ac72986f
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/b-var/main.c
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+#include "ops.h"
+
+int main(void)
+{
+	set(10);
+	printf("get(): %d\n", get());
+
+	age = 33;
+	print_age();
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/b-var/ops.h b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/b-var/ops.h
new file mode 100644
index 00000000..22d3d3ac
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/b-var/ops.h
@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef OPS_H_
+#define OPS_H_		1
+
+void init(void);
+void set(int value);
+int get(void);
+
+extern int age;
+void print_age(void);
+
+#endif
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/b-var/plain.c b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/b-var/plain.c
new file mode 100644
index 00000000..ce5252a4
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/b-var/plain.c
@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+
+static int age;
+
+void print_age(void)
+{
+	printf("age: %d\n", age);
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/c-var-2/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/c-var-2/.gitignore
new file mode 100644
index 00000000..95811e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/c-var-2/.gitignore
@@ -0,0 +1 @@
+/main
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/c-var-2/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/c-var-2/Makefile
new file mode 100644
index 00000000..5ed84dd5
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/c-var-2/Makefile
@@ -0,0 +1,21 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -no-pie -m32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: main
+
+main: main.o hidden.o plain.o
+	$(CC) $(LDFLAGS) -o $@ $^
+
+main.o: main.c ops.h
+
+hidden.o: hidden.c
+
+plain.o: plain.c
+
+clean:
+	-rm -f main main.o hidden.o plain.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/c-var-2/hidden.c b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/c-var-2/hidden.c
new file mode 100644
index 00000000..56b13cc7
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/c-var-2/hidden.c
@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+extern int hidden_value;
+
+void init(void)
+{
+	hidden_value = 0;
+}
+
+void set(int value)
+{
+	hidden_value = value;
+}
+
+int get(void)
+{
+	return hidden_value;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/c-var-2/main.c b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/c-var-2/main.c
new file mode 100644
index 00000000..ac72986f
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/c-var-2/main.c
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+#include "ops.h"
+
+int main(void)
+{
+	set(10);
+	printf("get(): %d\n", get());
+
+	age = 33;
+	print_age();
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/c-var-2/ops.h b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/c-var-2/ops.h
new file mode 100644
index 00000000..4c92c019
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/c-var-2/ops.h
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef OPS_H_
+#define OPS_H_		1
+
+void init(void);
+void set(int value);
+int get(void);
+
+void print_age(void);
+
+#endif
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/c-var-2/plain.c b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/c-var-2/plain.c
new file mode 100644
index 00000000..ce5252a4
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/export-fix/support/c-var-2/plain.c
@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+
+static int age;
+
+void print_age(void)
+{
+	printf("age: %d\n", age);
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/include-fix/README.md b/chapters/hardware-software-interface/linking/drills/tasks/include-fix/README.md
new file mode 100644
index 00000000..3adcc22f
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/include-fix/README.md
@@ -0,0 +1,10 @@
+# Warning (not an error)
+
+Access the directory `drills/tasks/include-fix/support/`.
+Run the `make` command.
+A warning appears, but it is from the preprocessing/compilation process.
+Resolve this warning by editing the `hello.c` file.
+
+**Bonus**: Fix the warning without using the `#include` directive.
+
+If you're having difficulties solving this exercise, go through [this](../../../reading/README.md) reading material.
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/include-fix/solution/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/include-fix/solution/.gitignore
new file mode 100644
index 00000000..e92569d0
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/include-fix/solution/.gitignore
@@ -0,0 +1 @@
+/hello
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/include-fix/solution/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/include-fix/solution/Makefile
new file mode 120000
index 00000000..a39be4f2
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/include-fix/solution/Makefile
@@ -0,0 +1 @@
+../support/Makefile
\ No newline at end of file
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/include-fix/solution/hello.c b/chapters/hardware-software-interface/linking/drills/tasks/include-fix/solution/hello.c
new file mode 100644
index 00000000..7a4ba956
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/include-fix/solution/hello.c
@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+
+static void hi(void)
+{
+	puts("Hi!");
+}
+
+static void bye(void)
+{
+	puts("Bye!");
+}
+
+int main(void)
+{
+	hi();
+	bye();
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/include-fix/support/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/include-fix/support/.gitignore
new file mode 100644
index 00000000..e92569d0
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/include-fix/support/.gitignore
@@ -0,0 +1 @@
+/hello
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/include-fix/support/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/include-fix/support/Makefile
new file mode 100644
index 00000000..cbd19a80
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/include-fix/support/Makefile
@@ -0,0 +1,17 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -no-pie -m32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: hello
+
+hello: hello.o
+	$(CC) $(LDFLAGS) -o $@ $^
+
+hello.o: hello.c
+
+clean:
+	-rm -f hello hello.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/include-fix/support/hello.c b/chapters/hardware-software-interface/linking/drills/tasks/include-fix/support/hello.c
new file mode 100644
index 00000000..ef112487
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/include-fix/support/hello.c
@@ -0,0 +1,17 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+static void hi(void)
+{
+	puts("Hi!");
+}
+
+static void bye(void)
+{
+	puts("Bye!");
+}
+
+int main(void)
+{
+	hi();
+	bye();
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/README.md b/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/README.md
new file mode 100644
index 00000000..22c03e33
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/README.md
@@ -0,0 +1,7 @@
+# Fixing Library Issues
+
+Access the directory `drills/tasks/lib-fix/support/`.
+Run the `make` command, interpret the encountered error, and resolve it by editing the `Makefile`.
+Refer to the `Makefile` in the directory `drills/tasks/multiple-link/support/example/c-lib/`.
+
+If you're having difficulties solving this exercise, go through [this](../../../reading/README.md) reading material.
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/solution/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/solution/.gitignore
new file mode 100644
index 00000000..95811e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/solution/.gitignore
@@ -0,0 +1 @@
+/main
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/solution/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/solution/Makefile
new file mode 100644
index 00000000..6ce73763
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/solution/Makefile
@@ -0,0 +1,24 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -no-pie -m32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: main
+
+main: main.o libops.a
+	$(CC) $(LDFLAGS) -o $@ $< -L. -lops
+
+main.o: main.c ops.h
+
+libops.a: add.o sub.o
+	ar rc $@ $^
+
+add.o: add.c
+
+sub.o: sub.c
+
+clean:
+	-rm -f main main.o libops.a add.o sub.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/solution/add.c b/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/solution/add.c
new file mode 100644
index 00000000..e0e2717e
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/solution/add.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int add(int a, int b)
+{
+	return a+b;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/solution/main.c b/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/solution/main.c
new file mode 100644
index 00000000..77b52aa2
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/solution/main.c
@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+#include "ops.h"
+
+int main(void)
+{
+	printf("add(10, 3): %d\n", add(10, 3));
+	printf("sub(10, 3): %d\n", sub(10, 3));
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/solution/ops.h b/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/solution/ops.h
new file mode 100644
index 00000000..f1ce5712
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/solution/ops.h
@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef OPS_H_
+#define OPS_H_		1
+
+int add(int a, int b);
+int sub(int a, int b);
+
+#endif
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/solution/sub.c b/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/solution/sub.c
new file mode 100644
index 00000000..9968ecd4
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/solution/sub.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int sub(int a, int b)
+{
+	return a-b;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/support/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/support/.gitignore
new file mode 100644
index 00000000..95811e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/support/.gitignore
@@ -0,0 +1 @@
+/main
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/support/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/support/Makefile
new file mode 100644
index 00000000..ae0a14ef
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/support/Makefile
@@ -0,0 +1,24 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -no-pie -m32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: main
+
+main: main.o libops.a
+	$(CC) $(LDFLAGS) -o $@ $< -lops
+
+main.o: main.c ops.h
+
+libops.a: add.o sub.o
+	ar rc $@ $^
+
+add.o: add.c
+
+sub.o: sub.c
+
+clean:
+	-rm -f main main.o libops.a add.o sub.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/support/add.c b/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/support/add.c
new file mode 100644
index 00000000..e0e2717e
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/support/add.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int add(int a, int b)
+{
+	return a+b;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/support/main.c b/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/support/main.c
new file mode 100644
index 00000000..77b52aa2
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/support/main.c
@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+#include "ops.h"
+
+int main(void)
+{
+	printf("add(10, 3): %d\n", add(10, 3));
+	printf("sub(10, 3): %d\n", sub(10, 3));
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/support/ops.h b/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/support/ops.h
new file mode 100644
index 00000000..f1ce5712
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/support/ops.h
@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef OPS_H_
+#define OPS_H_		1
+
+int add(int a, int b);
+int sub(int a, int b);
+
+#endif
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/support/sub.c b/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/support/sub.c
new file mode 100644
index 00000000..9968ecd4
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/lib-fix/support/sub.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int sub(int a, int b)
+{
+	return a-b;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/README.md b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/README.md
new file mode 100644
index 00000000..5467c1a1
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/README.md
@@ -0,0 +1,19 @@
+# Linking Multiple Files
+
+Access the directory `drills/tasks/multiple-link/support/example/`.
+We want to follow the linking commands from multiple C source files: `main.c`, `add.c`, `sub.c`.
+
+As in the previous exercises, there are three subdirectories for three different scenarios:
+
+* `a-no-header/`: external function declarations are made directly in the C source file (`main.c`)
+* `b-header/`: external function declarations are made in a separate header file (`ops.h`)
+* `c-lib/`: external function declarations are made in a separate header file, and linking is done using a static library
+
+In each subdirectory, we use the `make` command to compile the executable file `main`.
+
+Access the directory `drills/tasks/multiple-link/support/diy/`.
+We want to compile and link the source files in each subdirectory, following the model of the previous exercise.
+
+Copy the `Makefile` files and update them in each subdirectory to obtain the executable file.
+
+If you're having difficulties solving this exercise, go through [this](../../../reading/README.md) reading material.
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/a-no-header/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/a-no-header/.gitignore
new file mode 100644
index 00000000..95811e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/a-no-header/.gitignore
@@ -0,0 +1 @@
+/main
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/a-no-header/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/a-no-header/Makefile
new file mode 100644
index 00000000..d061297f
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/a-no-header/Makefile
@@ -0,0 +1,21 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -no-pie -m32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: main
+
+main: main.o mul.o div.o
+	$(CC) $(LDFLAGS) -o $@ $^
+
+main.o: main.c
+
+mul.o: mul.c
+
+div.o: div.c
+
+clean:
+	-rm -f main main.o mul.o div.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/a-no-header/div.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/a-no-header/div.c
new file mode 100644
index 00000000..e6008ce3
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/a-no-header/div.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int div(int a, int b)
+{
+	return a / b;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/a-no-header/main.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/a-no-header/main.c
new file mode 100644
index 00000000..f3f79c0b
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/a-no-header/main.c
@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+
+int mul(int a, int b);
+int div(int a, int b);
+
+int main(void)
+{
+	printf("mul(10, 5): %d\n", mul(10, 5));
+	printf("div(10, 5): %d\n", div(10, 5));
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/a-no-header/mul.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/a-no-header/mul.c
new file mode 100644
index 00000000..6bd2ce0c
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/a-no-header/mul.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int mul(int a, int b)
+{
+	return a * b;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/b-header/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/b-header/.gitignore
new file mode 100644
index 00000000..95811e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/b-header/.gitignore
@@ -0,0 +1 @@
+/main
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/b-header/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/b-header/Makefile
new file mode 100644
index 00000000..a02b4371
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/b-header/Makefile
@@ -0,0 +1,21 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -no-pie -m32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: main
+
+main: main.o mul.o div.o
+	$(CC) $(LDFLAGS) -o $@ $^
+
+main.o: main.c ops.h
+
+mul.o: mul.c
+
+div.o: div.c
+
+clean:
+	-rm -f main main.o mul.o div.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/b-header/div.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/b-header/div.c
new file mode 100644
index 00000000..e6008ce3
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/b-header/div.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int div(int a, int b)
+{
+	return a / b;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/b-header/main.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/b-header/main.c
new file mode 100644
index 00000000..5a550178
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/b-header/main.c
@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+#include "ops.h"
+
+int main(void)
+{
+	printf("mul(10, 5): %d\n", mul(10, 5));
+	printf("div(10, 5): %d\n", div(10, 5));
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/b-header/mul.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/b-header/mul.c
new file mode 100644
index 00000000..6bd2ce0c
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/b-header/mul.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int mul(int a, int b)
+{
+	return a * b;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/b-header/ops.h b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/b-header/ops.h
new file mode 100644
index 00000000..ae09152c
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/b-header/ops.h
@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef OPS_H_
+#define OPS_H_		1
+
+int mul(int a, int b);
+int div(int a, int b);
+
+#endif
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/c-lib/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/c-lib/.gitignore
new file mode 100644
index 00000000..da1bcad5
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/c-lib/.gitignore
@@ -0,0 +1,2 @@
+/main
+/libops.a
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/c-lib/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/c-lib/Makefile
new file mode 100644
index 00000000..913b8962
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/c-lib/Makefile
@@ -0,0 +1,24 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -no-pie -m32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: main
+
+main: main.o libops.a
+	$(CC) $(LDFLAGS) -o $@ $< -L. -lops
+
+main.o: main.c ops.h
+
+libops.a: mul.o div.o
+	ar rc $@ $^
+
+mul.o: mul.c
+
+div.o: div.c
+
+clean:
+	-rm -f main main.o libops.a mul.o div.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/c-lib/div.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/c-lib/div.c
new file mode 100644
index 00000000..e6008ce3
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/c-lib/div.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int div(int a, int b)
+{
+	return a / b;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/c-lib/main.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/c-lib/main.c
new file mode 100644
index 00000000..5a550178
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/c-lib/main.c
@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+#include "ops.h"
+
+int main(void)
+{
+	printf("mul(10, 5): %d\n", mul(10, 5));
+	printf("div(10, 5): %d\n", div(10, 5));
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/c-lib/mul.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/c-lib/mul.c
new file mode 100644
index 00000000..6bd2ce0c
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/c-lib/mul.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int mul(int a, int b)
+{
+	return a * b;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/c-lib/ops.h b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/c-lib/ops.h
new file mode 100644
index 00000000..ae09152c
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/solution/c-lib/ops.h
@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef OPS_H_
+#define OPS_H_		1
+
+int mul(int a, int b);
+int div(int a, int b);
+
+#endif
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/a-no-header/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/a-no-header/.gitignore
new file mode 100644
index 00000000..95811e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/a-no-header/.gitignore
@@ -0,0 +1 @@
+/main
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/a-no-header/div.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/a-no-header/div.c
new file mode 100644
index 00000000..e6008ce3
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/a-no-header/div.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int div(int a, int b)
+{
+	return a / b;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/a-no-header/main.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/a-no-header/main.c
new file mode 100644
index 00000000..f3f79c0b
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/a-no-header/main.c
@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+
+int mul(int a, int b);
+int div(int a, int b);
+
+int main(void)
+{
+	printf("mul(10, 5): %d\n", mul(10, 5));
+	printf("div(10, 5): %d\n", div(10, 5));
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/a-no-header/mul.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/a-no-header/mul.c
new file mode 100644
index 00000000..6bd2ce0c
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/a-no-header/mul.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int mul(int a, int b)
+{
+	return a * b;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/b-header/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/b-header/.gitignore
new file mode 100644
index 00000000..95811e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/b-header/.gitignore
@@ -0,0 +1 @@
+/main
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/b-header/div.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/b-header/div.c
new file mode 100644
index 00000000..e6008ce3
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/b-header/div.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int div(int a, int b)
+{
+	return a / b;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/b-header/main.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/b-header/main.c
new file mode 100644
index 00000000..5a550178
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/b-header/main.c
@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+#include "ops.h"
+
+int main(void)
+{
+	printf("mul(10, 5): %d\n", mul(10, 5));
+	printf("div(10, 5): %d\n", div(10, 5));
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/b-header/mul.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/b-header/mul.c
new file mode 100644
index 00000000..6bd2ce0c
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/b-header/mul.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int mul(int a, int b)
+{
+	return a * b;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/b-header/ops.h b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/b-header/ops.h
new file mode 100644
index 00000000..ae09152c
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/b-header/ops.h
@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef OPS_H_
+#define OPS_H_		1
+
+int mul(int a, int b);
+int div(int a, int b);
+
+#endif
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/c-lib/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/c-lib/.gitignore
new file mode 100644
index 00000000..da1bcad5
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/c-lib/.gitignore
@@ -0,0 +1,2 @@
+/main
+/libops.a
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/c-lib/div.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/c-lib/div.c
new file mode 100644
index 00000000..e6008ce3
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/c-lib/div.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int div(int a, int b)
+{
+	return a / b;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/c-lib/main.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/c-lib/main.c
new file mode 100644
index 00000000..5a550178
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/c-lib/main.c
@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+#include "ops.h"
+
+int main(void)
+{
+	printf("mul(10, 5): %d\n", mul(10, 5));
+	printf("div(10, 5): %d\n", div(10, 5));
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/c-lib/mul.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/c-lib/mul.c
new file mode 100644
index 00000000..6bd2ce0c
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/c-lib/mul.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int mul(int a, int b)
+{
+	return a * b;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/c-lib/ops.h b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/c-lib/ops.h
new file mode 100644
index 00000000..ae09152c
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/diy/c-lib/ops.h
@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef OPS_H_
+#define OPS_H_		1
+
+int mul(int a, int b);
+int div(int a, int b);
+
+#endif
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/a-no-header/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/a-no-header/.gitignore
new file mode 100644
index 00000000..95811e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/a-no-header/.gitignore
@@ -0,0 +1 @@
+/main
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/a-no-header/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/a-no-header/Makefile
new file mode 100644
index 00000000..61a30e12
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/a-no-header/Makefile
@@ -0,0 +1,21 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -no-pie -m32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: main
+
+main: main.o add.o sub.o
+	$(CC) $(LDFLAGS) -o $@ $^
+
+main.o: main.c
+
+add.o: add.c
+
+sub.o: sub.c
+
+clean:
+	-rm -f main main.o add.o sub.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/a-no-header/add.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/a-no-header/add.c
new file mode 100644
index 00000000..36db038f
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/a-no-header/add.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int add(int a, int b)
+{
+	return a + b;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/a-no-header/main.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/a-no-header/main.c
new file mode 100644
index 00000000..8fdec81f
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/a-no-header/main.c
@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+
+int add(int a, int b);
+int sub(int a, int b);
+
+int main(void)
+{
+	printf("add(10, 3): %d\n", add(10, 3));
+	printf("sub(10, 3): %d\n", sub(10, 3));
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/a-no-header/sub.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/a-no-header/sub.c
new file mode 100644
index 00000000..ecde8e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/a-no-header/sub.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int sub(int a, int b)
+{
+	return a - b;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/b-header/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/b-header/.gitignore
new file mode 100644
index 00000000..95811e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/b-header/.gitignore
@@ -0,0 +1 @@
+/main
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/b-header/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/b-header/Makefile
new file mode 100644
index 00000000..8dfe243f
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/b-header/Makefile
@@ -0,0 +1,21 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -no-pie -m32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: main
+
+main: main.o add.o sub.o
+	$(CC) $(LDFLAGS) -o $@ $^
+
+main.o: main.c ops.h
+
+add.o: add.c
+
+sub.o: sub.c
+
+clean:
+	-rm -f main main.o add.o sub.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/b-header/add.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/b-header/add.c
new file mode 100644
index 00000000..36db038f
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/b-header/add.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int add(int a, int b)
+{
+	return a + b;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/b-header/main.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/b-header/main.c
new file mode 100644
index 00000000..77b52aa2
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/b-header/main.c
@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+#include "ops.h"
+
+int main(void)
+{
+	printf("add(10, 3): %d\n", add(10, 3));
+	printf("sub(10, 3): %d\n", sub(10, 3));
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/b-header/ops.h b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/b-header/ops.h
new file mode 100644
index 00000000..f1ce5712
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/b-header/ops.h
@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef OPS_H_
+#define OPS_H_		1
+
+int add(int a, int b);
+int sub(int a, int b);
+
+#endif
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/b-header/sub.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/b-header/sub.c
new file mode 100644
index 00000000..ecde8e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/b-header/sub.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int sub(int a, int b)
+{
+	return a - b;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/c-lib/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/c-lib/.gitignore
new file mode 100644
index 00000000..da1bcad5
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/c-lib/.gitignore
@@ -0,0 +1,2 @@
+/main
+/libops.a
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/c-lib/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/c-lib/Makefile
new file mode 100644
index 00000000..6ce73763
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/c-lib/Makefile
@@ -0,0 +1,24 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -no-pie -m32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: main
+
+main: main.o libops.a
+	$(CC) $(LDFLAGS) -o $@ $< -L. -lops
+
+main.o: main.c ops.h
+
+libops.a: add.o sub.o
+	ar rc $@ $^
+
+add.o: add.c
+
+sub.o: sub.c
+
+clean:
+	-rm -f main main.o libops.a add.o sub.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/c-lib/add.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/c-lib/add.c
new file mode 100644
index 00000000..36db038f
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/c-lib/add.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int add(int a, int b)
+{
+	return a + b;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/c-lib/main.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/c-lib/main.c
new file mode 100644
index 00000000..77b52aa2
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/c-lib/main.c
@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+#include "ops.h"
+
+int main(void)
+{
+	printf("add(10, 3): %d\n", add(10, 3));
+	printf("sub(10, 3): %d\n", sub(10, 3));
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/c-lib/ops.h b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/c-lib/ops.h
new file mode 100644
index 00000000..f1ce5712
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/c-lib/ops.h
@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef OPS_H_
+#define OPS_H_		1
+
+int add(int a, int b);
+int sub(int a, int b);
+
+#endif
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/c-lib/sub.c b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/c-lib/sub.c
new file mode 100644
index 00000000..ecde8e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/multiple-link/support/example/c-lib/sub.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int sub(int a, int b)
+{
+	return a - b;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/obj-link-dev/README.md b/chapters/hardware-software-interface/linking/drills/tasks/obj-link-dev/README.md
new file mode 100644
index 00000000..6acbd113
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/obj-link-dev/README.md
@@ -0,0 +1,14 @@
+# Linking an Object File (without Source Code)
+
+Access the directory `drills/tasks/obj-link-dev/support/`.
+The file `shop.o` exposes an interface (functions and variables) that allows displaying messages.
+Edit the `main.c` file to properly call the exposed interface and display the messages:
+
+```bash
+price is 21
+quantity is 42
+```
+
+Explore the interface and the content of the functions in the `shop.o` file using `nm` and `objdump`.
+
+If you're having difficulties solving this exercise, go through [this](../../../reading/README.md) reading material.
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/obj-link-dev/solution/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/obj-link-dev/solution/.gitignore
new file mode 100644
index 00000000..95811e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/obj-link-dev/solution/.gitignore
@@ -0,0 +1 @@
+/main
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/obj-link-dev/solution/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/obj-link-dev/solution/Makefile
new file mode 120000
index 00000000..a39be4f2
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/obj-link-dev/solution/Makefile
@@ -0,0 +1 @@
+../support/Makefile
\ No newline at end of file
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/obj-link-dev/solution/main.c b/chapters/hardware-software-interface/linking/drills/tasks/obj-link-dev/solution/main.c
new file mode 100644
index 00000000..a474d2e7
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/obj-link-dev/solution/main.c
@@ -0,0 +1,24 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+/*
+ * Use 'nm' to find symbols in shop.o
+ * Then, use 'objdump' to inspect the object
+ * code of the functions, in order to get
+ * the prototypes.
+ */
+extern int set_price(int price);
+extern void print_price(void);
+
+extern int qty;
+extern void print_quantity(void);
+
+int main(void)
+{
+	set_price(21);
+	print_price();
+
+	qty = 42;
+	print_quantity();
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/obj-link-dev/support/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/obj-link-dev/support/.gitignore
new file mode 100644
index 00000000..95811e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/obj-link-dev/support/.gitignore
@@ -0,0 +1 @@
+/main
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/obj-link-dev/support/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/obj-link-dev/support/Makefile
new file mode 100644
index 00000000..96218971
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/obj-link-dev/support/Makefile
@@ -0,0 +1,15 @@
+CFLAGS = -Wall -g
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: main
+
+main: main.o shop.o
+
+main.o: main.c
+
+clean:
+	-rm -f main main.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/obj-link-dev/support/main.c b/chapters/hardware-software-interface/linking/drills/tasks/obj-link-dev/support/main.c
new file mode 100644
index 00000000..0328c1af
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/obj-link-dev/support/main.c
@@ -0,0 +1,13 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int main(void)
+{
+	/*
+	 * TODO: Make it so you print:
+	 *    price is 21
+	 *    quantity is 42
+	 * without directly calling a printing function.
+	 */
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/README.md b/chapters/hardware-software-interface/linking/drills/tasks/single-link/README.md
new file mode 100644
index 00000000..a37a32c0
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/README.md
@@ -0,0 +1,34 @@
+# Linking a Single File
+
+Access the directory `drills/tasks/single-link/support/example/`.
+We want to follow the linking commands for a single C source file.
+The source file is `hello.c`.
+
+In the three subdirectories, you will find support files for the following scenarios:
+
+- `a-dynamic/`: creating a dynamic executable file
+- `b-static/`: creating a static executable file
+- `c-standalone/`: creating a standalone executable file without the standard C library
+
+In each subdirectory, we use the `make` command to compile the executable file `hello`.
+We use the command `file hello` to check whether the file is compiled dynamically or statically.
+
+In the `Makefile` files, the linking command uses `gcc`.
+An equivalent command that directly uses `ld` is commented out.
+To track the direct usage of `ld`, we can comment out the `gcc` command and uncomment the `ld` command.
+
+In the case of `c-standalone/`, since we are not using the standard C library or C runtime library, we need to replace their functionalities.
+The functionalities are replaced in the `start.asm` and `puts.asm` files.
+These files implement the `_start` function/symbol and the `puts` function, respectively.
+The `_start` function/symbol is, by default, the entry point of an executable program.
+The `_start` function is responsible for calling the `main` function and terminating the program.
+Because there is no standard library, these two files are written in assembly language and use system calls.
+
+**Bonus**: Add a command in the `Makefile` in the `c-standalone/` directory that explicitly uses `ld` for linking.
+
+Access the directory `drills/tasks/single-link/support/diy/`.
+We want to compile and link the source files in each subdirectory, following the model of the previous exercise.
+
+Copy the `Makefile` files and update them in each subdirectory to obtain the executable file.
+
+If you're having difficulties solving this exercise, go through [this](../../../reading/README.md) reading material.
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/a-dynamic/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/a-dynamic/.gitignore
new file mode 100644
index 00000000..04b61914
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/a-dynamic/.gitignore
@@ -0,0 +1 @@
+/name
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/a-dynamic/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/a-dynamic/Makefile
new file mode 100644
index 00000000..2b196f0a
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/a-dynamic/Makefile
@@ -0,0 +1,18 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -no-pie -m32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: name
+
+name: name.o
+	$(CC) $(LDFLAGS) -o $@ $^
+	#ld -dynamic-linker /lib/ld-linux.so.2 -m elf_i386 -o $@ /usr/lib32/crt1.o /usr/lib32/crti.o $^ -lc /usr/lib32/crtn.o
+
+name.o: name.c
+
+clean:
+	-rm -f name name.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/a-dynamic/name.c b/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/a-dynamic/name.c
new file mode 100644
index 00000000..b09291fa
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/a-dynamic/name.c
@@ -0,0 +1,9 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+
+int main(void)
+{
+	puts("Hi, my name is TODO.");
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/b-static/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/b-static/.gitignore
new file mode 100644
index 00000000..04b61914
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/b-static/.gitignore
@@ -0,0 +1 @@
+/name
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/b-static/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/b-static/Makefile
new file mode 100644
index 00000000..e1e86265
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/b-static/Makefile
@@ -0,0 +1,18 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -static -no-pie -m32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: name
+
+name: name.o
+	$(CC) $(LDFLAGS) -o $@ $^
+	#ld -static -m elf_i386 -L/usr/lib/gcc/x86_64-linux-gnu/7/32/ -o $@ /usr/lib32/crt1.o /usr/lib32/crti.o $^ --start-group -lc -lgcc -lgcc_eh --end-group /usr/lib32/crtn.o
+
+name.o: name.c
+
+clean:
+	-rm -f name name.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/b-static/name.c b/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/b-static/name.c
new file mode 100644
index 00000000..b09291fa
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/b-static/name.c
@@ -0,0 +1,9 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+
+int main(void)
+{
+	puts("Hi, my name is TODO.");
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/c-standalone/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/c-standalone/.gitignore
new file mode 100644
index 00000000..04b61914
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/c-standalone/.gitignore
@@ -0,0 +1 @@
+/name
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/c-standalone/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/c-standalone/Makefile
new file mode 100644
index 00000000..a52306c0
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/c-standalone/Makefile
@@ -0,0 +1,24 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -nostdinc -nostdlib -no-pie -m32
+AS = nasm
+ASFLAGS = -f elf32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: name
+
+name: name.o start.o puts.o
+
+name.o: name.c
+
+start.o: start.asm
+	$(AS) $(ASFLAGS) -o $@ $<
+
+puts.o: puts.asm
+	$(AS) $(ASFLAGS) -o $@ $<
+
+clean:
+	-rm -f name name.o start.o puts.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/c-standalone/name.c b/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/c-standalone/name.c
new file mode 100644
index 00000000..57a203f1
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/c-standalone/name.c
@@ -0,0 +1,9 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int puts(const char *);
+
+int main(void)
+{
+	puts("Hi, my name is TODO.\n");
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/c-standalone/puts.asm b/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/c-standalone/puts.asm
new file mode 100644
index 00000000..57a09ded
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/c-standalone/puts.asm
@@ -0,0 +1,51 @@
+; SPDX-License-Identifier: BSD-3-Clause
+
+section .text
+
+global puts
+
+; /usr/include/x86_64-linux-gnu/asm/unistd_32.h
+__NR_write equ 4
+
+; Argument is message to be printed to standard output.
+puts:
+    push ebp
+    mov ebp, esp
+
+    ; Call __NR_write(1, message, message_len) (system call).
+    ;
+    ; Use x86 Linux system call convention.
+    ; https://en.wikibooks.org/wiki/X86_Assembly/Interfacing_with_Linux#Making_a_system_call
+    ;
+    ; eax stores the system call id.
+    ; ebx stores the first system call argument: 1 (standard output).
+    ; ecx stores the second system call argument: message.
+    ; edc stores the third system call argument: message length.
+
+    ; Store the write system call id in eax.
+    mov eax, __NR_write
+
+    ; Store standard output file descriptor (1) in ebx.
+    mov ebx, 1
+
+    ; Store function argument (message) in ecx.
+    mov ecx, [ebp + 8]
+
+    ; Compute message length in edx.
+    ; Find NUL byte address of message using edi. Start from message address (ecx).
+    ; Then edx <- edi - ecx.
+    mov edi, ecx
+    dec edi
+again:
+    inc edi
+    cmp byte [edi], 0
+    jne again
+
+    mov edx, edi
+    sub edx, ecx
+
+    ; Do system call.
+    int 0x80
+
+    leave
+    ret
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/c-standalone/start.asm b/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/c-standalone/start.asm
new file mode 100644
index 00000000..c384e42b
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/solution/c-standalone/start.asm
@@ -0,0 +1,30 @@
+; SPDX-License-Identifier: BSD-3-Clause
+
+extern main
+
+section .text
+
+; /usr/include/x86_64-linux-gnu/asm/unistd_32.h
+__NR_exit equ 1
+
+global _start
+
+_start:
+    call main
+
+    ; Call __NR_exit(main_return_value) (system call).
+    ;
+    ; Use x86 Linux system call convention.
+    ; https://en.wikibooks.org/wiki/X86_Assembly/Interfacing_with_Linux#Making_a_system_call
+    ;
+    ; ebx stores the first system call argument.
+    ; eax stores the system call id.
+
+    ; eax is main return value. Store it in ebx.
+    mov ebx, eax
+
+    ; Store the exit system call id in rax.
+    mov eax, __NR_exit
+
+    ; Do system call.
+    int 0x80
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/diy/a-dynamic/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/diy/a-dynamic/.gitignore
new file mode 100644
index 00000000..04b61914
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/diy/a-dynamic/.gitignore
@@ -0,0 +1 @@
+/name
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/diy/a-dynamic/name.c b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/diy/a-dynamic/name.c
new file mode 100644
index 00000000..b09291fa
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/diy/a-dynamic/name.c
@@ -0,0 +1,9 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+
+int main(void)
+{
+	puts("Hi, my name is TODO.");
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/diy/b-static/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/diy/b-static/.gitignore
new file mode 100644
index 00000000..04b61914
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/diy/b-static/.gitignore
@@ -0,0 +1 @@
+/name
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/diy/b-static/name.c b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/diy/b-static/name.c
new file mode 100644
index 00000000..b09291fa
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/diy/b-static/name.c
@@ -0,0 +1,9 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+
+int main(void)
+{
+	puts("Hi, my name is TODO.");
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/diy/c-standalone/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/diy/c-standalone/.gitignore
new file mode 100644
index 00000000..04b61914
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/diy/c-standalone/.gitignore
@@ -0,0 +1 @@
+/name
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/diy/c-standalone/name.c b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/diy/c-standalone/name.c
new file mode 100644
index 00000000..57a203f1
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/diy/c-standalone/name.c
@@ -0,0 +1,9 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int puts(const char *);
+
+int main(void)
+{
+	puts("Hi, my name is TODO.\n");
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/diy/c-standalone/puts.asm b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/diy/c-standalone/puts.asm
new file mode 100644
index 00000000..57a09ded
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/diy/c-standalone/puts.asm
@@ -0,0 +1,51 @@
+; SPDX-License-Identifier: BSD-3-Clause
+
+section .text
+
+global puts
+
+; /usr/include/x86_64-linux-gnu/asm/unistd_32.h
+__NR_write equ 4
+
+; Argument is message to be printed to standard output.
+puts:
+    push ebp
+    mov ebp, esp
+
+    ; Call __NR_write(1, message, message_len) (system call).
+    ;
+    ; Use x86 Linux system call convention.
+    ; https://en.wikibooks.org/wiki/X86_Assembly/Interfacing_with_Linux#Making_a_system_call
+    ;
+    ; eax stores the system call id.
+    ; ebx stores the first system call argument: 1 (standard output).
+    ; ecx stores the second system call argument: message.
+    ; edc stores the third system call argument: message length.
+
+    ; Store the write system call id in eax.
+    mov eax, __NR_write
+
+    ; Store standard output file descriptor (1) in ebx.
+    mov ebx, 1
+
+    ; Store function argument (message) in ecx.
+    mov ecx, [ebp + 8]
+
+    ; Compute message length in edx.
+    ; Find NUL byte address of message using edi. Start from message address (ecx).
+    ; Then edx <- edi - ecx.
+    mov edi, ecx
+    dec edi
+again:
+    inc edi
+    cmp byte [edi], 0
+    jne again
+
+    mov edx, edi
+    sub edx, ecx
+
+    ; Do system call.
+    int 0x80
+
+    leave
+    ret
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/diy/c-standalone/start.asm b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/diy/c-standalone/start.asm
new file mode 100644
index 00000000..c384e42b
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/diy/c-standalone/start.asm
@@ -0,0 +1,30 @@
+; SPDX-License-Identifier: BSD-3-Clause
+
+extern main
+
+section .text
+
+; /usr/include/x86_64-linux-gnu/asm/unistd_32.h
+__NR_exit equ 1
+
+global _start
+
+_start:
+    call main
+
+    ; Call __NR_exit(main_return_value) (system call).
+    ;
+    ; Use x86 Linux system call convention.
+    ; https://en.wikibooks.org/wiki/X86_Assembly/Interfacing_with_Linux#Making_a_system_call
+    ;
+    ; ebx stores the first system call argument.
+    ; eax stores the system call id.
+
+    ; eax is main return value. Store it in ebx.
+    mov ebx, eax
+
+    ; Store the exit system call id in rax.
+    mov eax, __NR_exit
+
+    ; Do system call.
+    int 0x80
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/a-dynamic/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/a-dynamic/.gitignore
new file mode 100644
index 00000000..e92569d0
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/a-dynamic/.gitignore
@@ -0,0 +1 @@
+/hello
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/a-dynamic/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/a-dynamic/Makefile
new file mode 100644
index 00000000..3ea76660
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/a-dynamic/Makefile
@@ -0,0 +1,18 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -no-pie -m32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: hello
+
+hello: hello.o
+	$(CC) $(LDFLAGS) -o $@ $^
+	#ld -dynamic-linker /lib/ld-linux.so.2 -m elf_i386 -o $@ /usr/lib32/crt1.o /usr/lib32/crti.o $^ -lc /usr/lib32/crtn.o
+
+hello.o: hello.c
+
+clean:
+	-rm -f hello hello.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/a-dynamic/hello.c b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/a-dynamic/hello.c
new file mode 100644
index 00000000..772630f3
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/a-dynamic/hello.c
@@ -0,0 +1,9 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+
+int main(void)
+{
+	puts("Hello, World!");
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/b-static/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/b-static/.gitignore
new file mode 100644
index 00000000..e92569d0
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/b-static/.gitignore
@@ -0,0 +1 @@
+/hello
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/b-static/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/b-static/Makefile
new file mode 100644
index 00000000..0ddd2ba7
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/b-static/Makefile
@@ -0,0 +1,18 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -static -no-pie -m32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: hello
+
+hello: hello.o
+	$(CC) $(LDFLAGS) -o $@ $^
+	#ld -static -m elf_i386 -L/usr/lib/gcc/x86_64-linux-gnu/7/32/ -o $@ /usr/lib32/crt1.o /usr/lib32/crti.o $^ --start-group -lc -lgcc -lgcc_eh --end-group /usr/lib32/crtn.o
+
+hello.o: hello.c
+
+clean:
+	-rm -f hello hello.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/b-static/hello.c b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/b-static/hello.c
new file mode 100644
index 00000000..772630f3
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/b-static/hello.c
@@ -0,0 +1,9 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+
+int main(void)
+{
+	puts("Hello, World!");
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/c-standalone/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/c-standalone/.gitignore
new file mode 100644
index 00000000..e92569d0
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/c-standalone/.gitignore
@@ -0,0 +1 @@
+/hello
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/c-standalone/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/c-standalone/Makefile
new file mode 100644
index 00000000..4bdeb57d
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/c-standalone/Makefile
@@ -0,0 +1,24 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -nostdinc -nostdlib -no-pie -m32
+AS = nasm
+ASFLAGS = -f elf32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: hello
+
+hello: hello.o start.o puts.o
+
+hello.o: hello.c
+
+start.o: start.asm
+	$(AS) $(ASFLAGS) -o $@ $<
+
+puts.o: puts.asm
+	$(AS) $(ASFLAGS) -o $@ $<
+
+clean:
+	-rm -f hello hello.o start.o puts.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/c-standalone/hello.c b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/c-standalone/hello.c
new file mode 100644
index 00000000..8925010a
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/c-standalone/hello.c
@@ -0,0 +1,9 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int puts(const char *);
+
+int main(void)
+{
+	puts("Hello, World!\n");
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/c-standalone/puts.asm b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/c-standalone/puts.asm
new file mode 100644
index 00000000..57a09ded
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/c-standalone/puts.asm
@@ -0,0 +1,51 @@
+; SPDX-License-Identifier: BSD-3-Clause
+
+section .text
+
+global puts
+
+; /usr/include/x86_64-linux-gnu/asm/unistd_32.h
+__NR_write equ 4
+
+; Argument is message to be printed to standard output.
+puts:
+    push ebp
+    mov ebp, esp
+
+    ; Call __NR_write(1, message, message_len) (system call).
+    ;
+    ; Use x86 Linux system call convention.
+    ; https://en.wikibooks.org/wiki/X86_Assembly/Interfacing_with_Linux#Making_a_system_call
+    ;
+    ; eax stores the system call id.
+    ; ebx stores the first system call argument: 1 (standard output).
+    ; ecx stores the second system call argument: message.
+    ; edc stores the third system call argument: message length.
+
+    ; Store the write system call id in eax.
+    mov eax, __NR_write
+
+    ; Store standard output file descriptor (1) in ebx.
+    mov ebx, 1
+
+    ; Store function argument (message) in ecx.
+    mov ecx, [ebp + 8]
+
+    ; Compute message length in edx.
+    ; Find NUL byte address of message using edi. Start from message address (ecx).
+    ; Then edx <- edi - ecx.
+    mov edi, ecx
+    dec edi
+again:
+    inc edi
+    cmp byte [edi], 0
+    jne again
+
+    mov edx, edi
+    sub edx, ecx
+
+    ; Do system call.
+    int 0x80
+
+    leave
+    ret
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/c-standalone/start.asm b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/c-standalone/start.asm
new file mode 100644
index 00000000..c384e42b
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/single-link/support/example/c-standalone/start.asm
@@ -0,0 +1,30 @@
+; SPDX-License-Identifier: BSD-3-Clause
+
+extern main
+
+section .text
+
+; /usr/include/x86_64-linux-gnu/asm/unistd_32.h
+__NR_exit equ 1
+
+global _start
+
+_start:
+    call main
+
+    ; Call __NR_exit(main_return_value) (system call).
+    ;
+    ; Use x86 Linux system call convention.
+    ; https://en.wikibooks.org/wiki/X86_Assembly/Interfacing_with_Linux#Making_a_system_call
+    ;
+    ; ebx stores the first system call argument.
+    ; eax stores the system call id.
+
+    ; eax is main return value. Store it in ebx.
+    mov ebx, eax
+
+    ; Store the exit system call id in rax.
+    mov eax, __NR_exit
+
+    ; Do system call.
+    int 0x80
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/README.md b/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/README.md
new file mode 100644
index 00000000..8ec82d4e
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/README.md
@@ -0,0 +1,6 @@
+# Using Symbols (Variables and Functions)
+
+Access the directory `drills/tasks/10-var-func-fix/support/`.
+Run the `make` command, interpret the encountered error, and resolve it by editing the source files.
+
+If you're having difficulties solving this exercise, go through [this](../../../reading/README.md) reading material.
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/solution/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/solution/.gitignore
new file mode 100644
index 00000000..95811e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/solution/.gitignore
@@ -0,0 +1 @@
+/main
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/solution/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/solution/Makefile
new file mode 120000
index 00000000..a39be4f2
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/solution/Makefile
@@ -0,0 +1 @@
+../support/Makefile
\ No newline at end of file
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/solution/main.c b/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/solution/main.c
new file mode 100644
index 00000000..2b6db291
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/solution/main.c
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+#include "state.h"
+
+int main(void)
+{
+	size_t i;
+
+	init_shopping();
+	for (i = 0; i < sizeof(shopping_list) / sizeof(shopping_list[0]); i++)
+		printf("%s\n", shopping_list[i]);
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/solution/state.c b/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/solution/state.c
new file mode 100644
index 00000000..f03442d2
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/solution/state.c
@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+const char *shopping_list[3];
+
+void init_shopping(void)
+{
+	shopping_list[0] = "cheese";
+	shopping_list[1] = "wine";
+	shopping_list[2] = "dessert";
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/solution/state.h b/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/solution/state.h
new file mode 100644
index 00000000..7b1b089d
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/solution/state.h
@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef STATE_H_
+#define STATE_H_	1
+
+void init_shopping(void);
+extern const char *shopping_list[3];
+
+#endif
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/support/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/support/.gitignore
new file mode 100644
index 00000000..95811e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/support/.gitignore
@@ -0,0 +1 @@
+/main
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/support/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/support/Makefile
new file mode 100644
index 00000000..e6c47716
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/support/Makefile
@@ -0,0 +1,19 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -no-pie -m32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: main
+
+main: main.o state.o
+	$(CC) $(LDFLAGS) -o $@ $^
+
+main.o: main.c state.h
+
+state.o: state.c
+
+clean:
+	-rm -f main main.o state.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/support/main.c b/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/support/main.c
new file mode 100644
index 00000000..2b6db291
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/support/main.c
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+#include "state.h"
+
+int main(void)
+{
+	size_t i;
+
+	init_shopping();
+	for (i = 0; i < sizeof(shopping_list) / sizeof(shopping_list[0]); i++)
+		printf("%s\n", shopping_list[i]);
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/support/state.c b/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/support/state.c
new file mode 100644
index 00000000..73b9002c
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/support/state.c
@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+const char *init_shopping[3];
+
+void shopping_list(void)
+{
+	init_shopping[0] = "cheese";
+	init_shopping[1] = "wine";
+	init_shopping[2] = "dessert";
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/support/state.h b/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/support/state.h
new file mode 100644
index 00000000..7b1b089d
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/var-func-fix/support/state.h
@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef STATE_H_
+#define STATE_H_	1
+
+void init_shopping(void);
+extern const char *shopping_list[3];
+
+#endif
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/README.md b/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/README.md
new file mode 100644
index 00000000..8b67d1b2
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/README.md
@@ -0,0 +1,19 @@
+# Using Variables
+
+Access the directory `drills/tasks/vars-obs/support/`.
+We want to track the use of global variables, both exported and non-exported.
+
+In the `hidden.c` file, we have the static (non-exported) variable `hidden_value`.
+This variable is modified and accessed using non-exported functions: `init()`, `get()`, `set()`.
+
+In the `plain.c` file, we have the exported variable `age`.
+This variable can be modified and accessed directly.
+
+These variables are used directly (`age`) or indirectly (`hidden_value`) in the `main.c` file.
+To use them, the functions and variables are declared in the `ops.h` file.
+A function is declared by specifying the header.
+A variable is declared by prefixing it with `extern`.
+
+Modify `main.c` such that `hidden_value` is set to 10 and `age` is set to 33.
+
+If you're having difficulties solving this exercise, go through [this](../../../reading/README.md) reading material.
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/solution/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/solution/.gitignore
new file mode 100644
index 00000000..95811e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/solution/.gitignore
@@ -0,0 +1 @@
+/main
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/solution/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/solution/Makefile
new file mode 120000
index 00000000..a39be4f2
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/solution/Makefile
@@ -0,0 +1 @@
+../support/Makefile
\ No newline at end of file
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/solution/hidden.c b/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/solution/hidden.c
new file mode 100644
index 00000000..a1e11369
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/solution/hidden.c
@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+static int hidden_value;
+
+void init(void)
+{
+	hidden_value = 0;
+}
+
+void set(int value)
+{
+	hidden_value = value;
+}
+
+int get(void)
+{
+	return hidden_value;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/solution/main.c b/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/solution/main.c
new file mode 100644
index 00000000..3d775e22
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/solution/main.c
@@ -0,0 +1,17 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+#include "ops.h"
+
+// Function used to validate the result.
+extern void check_result(void);
+
+int main(void)
+{
+    set(10);
+	age = 33;
+
+	check_result();
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/solution/ops.h b/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/solution/ops.h
new file mode 100644
index 00000000..22d3d3ac
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/solution/ops.h
@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef OPS_H_
+#define OPS_H_		1
+
+void init(void);
+void set(int value);
+int get(void);
+
+extern int age;
+void print_age(void);
+
+#endif
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/solution/plain.c b/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/solution/plain.c
new file mode 100644
index 00000000..b620ed57
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/solution/plain.c
@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+
+int age;
+
+void print_age(void)
+{
+	printf("age: %d\n", age);
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/support/.gitignore b/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/support/.gitignore
new file mode 100644
index 00000000..95811e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/support/.gitignore
@@ -0,0 +1 @@
+/main
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/support/Makefile b/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/support/Makefile
new file mode 100644
index 00000000..dbca39f0
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/support/Makefile
@@ -0,0 +1,21 @@
+CFLAGS = -fno-PIC -m32 -g
+LDFLAGS = -no-pie -m32
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: main
+
+main: main.o hidden.o plain.o checker.o
+	$(CC) $(LDFLAGS) -o $@ $^
+
+main.o: main.c ops.h
+
+hidden.o: hidden.c
+
+plain.o: plain.c
+
+clean:
+	-rm -f main main.o hidden.o plain.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/support/hidden.c b/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/support/hidden.c
new file mode 100644
index 00000000..a1e11369
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/support/hidden.c
@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+static int hidden_value;
+
+void init(void)
+{
+	hidden_value = 0;
+}
+
+void set(int value)
+{
+	hidden_value = value;
+}
+
+int get(void)
+{
+	return hidden_value;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/support/main.c b/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/support/main.c
new file mode 100644
index 00000000..6ae481b4
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/support/main.c
@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+#include "ops.h"
+
+// Function used to validate the result.
+extern void check_result(void);
+
+int main(void)
+{
+	check_result();
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/support/ops.h b/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/support/ops.h
new file mode 100644
index 00000000..22d3d3ac
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/support/ops.h
@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef OPS_H_
+#define OPS_H_		1
+
+void init(void);
+void set(int value);
+int get(void);
+
+extern int age;
+void print_age(void);
+
+#endif
diff --git a/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/support/plain.c b/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/support/plain.c
new file mode 100644
index 00000000..b620ed57
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/drills/tasks/vars-obs/support/plain.c
@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+
+int age;
+
+void print_age(void)
+{
+	printf("age: %d\n", age);
+}
diff --git a/chapters/hardware-software-interface/linking/guides/cpp-obs/README.md b/chapters/hardware-software-interface/linking/guides/cpp-obs/README.md
new file mode 100644
index 00000000..90ea740f
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/guides/cpp-obs/README.md
@@ -0,0 +1,28 @@
+# Linking C and C++
+
+Access the directory `drills/tasks/cpp-obs/support/`.
+We want to observe how linking is performed with mixed sources: C and C++.
+
+In the `bad/` subdirectory, we have two directories, `c-calls-cpp/` and `cpp-calls-c/`, where we combine C and C++ sources.
+In both cases, using `make` displays errors.
+This occurs because C++ symbols are *mangled*.
+
+If we use the `nm` command on object modules obtained from C source code, we get:
+
+```console
+$ nm add.o
+0000000000000000 T _Z3addii
+
+$ nm sub.o
+0000000000000000 T _Z3subii
+```
+
+The symbol names are not `add` and `sub`, but rather `_Z3addii` and `_Z3subii`.
+C++ symbol names are *mangled* and define the function signature.
+This allows for functions with the same name but different signatures.
+Details about *name mangling* can be found [here](https://en.wikipedia.org/wiki/Name_mangling).
+
+To resolve this, symbols defined in C and imported into C++, or vice versa, must be prefixed with the directive `extern "C"`.
+This way, the C++ compiler will use simple names for the imported/exported symbols, allowing them to be used together with C modules.
+This is implemented in the `good/` subdirectory.
+Details about the `extern "C"` directive can be found [here](https://stackoverflow.com/a/1041880/4804196).
diff --git a/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/c-calls-cpp/.gitignore b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/c-calls-cpp/.gitignore
new file mode 100644
index 00000000..95811e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/c-calls-cpp/.gitignore
@@ -0,0 +1 @@
+/main
diff --git a/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/c-calls-cpp/Makefile b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/c-calls-cpp/Makefile
new file mode 100644
index 00000000..63092931
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/c-calls-cpp/Makefile
@@ -0,0 +1,22 @@
+CFLAGS = -Wall -g
+CXXFLAGS = -Wall -g
+LDFLAGS = -lstdc++
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: main
+
+main: main.o add.o sub.o
+	$(CC) $(LDFLAGS) -o $@ $^
+
+main.o: main.c ops.h
+
+add.o: add.cpp
+
+sub.o: sub.cpp
+
+clean:
+	-rm -f main main.o add.o sub.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/c-calls-cpp/add.cpp b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/c-calls-cpp/add.cpp
new file mode 100644
index 00000000..36db038f
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/c-calls-cpp/add.cpp
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int add(int a, int b)
+{
+	return a + b;
+}
diff --git a/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/c-calls-cpp/main.c b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/c-calls-cpp/main.c
new file mode 100644
index 00000000..77b52aa2
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/c-calls-cpp/main.c
@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+#include "ops.h"
+
+int main(void)
+{
+	printf("add(10, 3): %d\n", add(10, 3));
+	printf("sub(10, 3): %d\n", sub(10, 3));
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/c-calls-cpp/ops.h b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/c-calls-cpp/ops.h
new file mode 100644
index 00000000..f1ce5712
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/c-calls-cpp/ops.h
@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef OPS_H_
+#define OPS_H_		1
+
+int add(int a, int b);
+int sub(int a, int b);
+
+#endif
diff --git a/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/c-calls-cpp/sub.cpp b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/c-calls-cpp/sub.cpp
new file mode 100644
index 00000000..ecde8e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/c-calls-cpp/sub.cpp
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int sub(int a, int b)
+{
+	return a - b;
+}
diff --git a/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/cpp-calls-c/.gitignore b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/cpp-calls-c/.gitignore
new file mode 100644
index 00000000..95811e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/cpp-calls-c/.gitignore
@@ -0,0 +1 @@
+/main
diff --git a/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/cpp-calls-c/Makefile b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/cpp-calls-c/Makefile
new file mode 100644
index 00000000..faa510b3
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/cpp-calls-c/Makefile
@@ -0,0 +1,21 @@
+CFLAGS = -Wall -g
+CXXFLAGS = -Wall -g
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: main
+
+main: main.o add.o sub.o
+	$(CXX) $(LDFLAGS) -o $@ $^
+
+main.o: main.cpp ops.h
+
+add.o: add.c
+
+sub.o: sub.c
+
+clean:
+	-rm -f main main.o add.o sub.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/cpp-calls-c/add.c b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/cpp-calls-c/add.c
new file mode 100644
index 00000000..36db038f
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/cpp-calls-c/add.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int add(int a, int b)
+{
+	return a + b;
+}
diff --git a/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/cpp-calls-c/main.cpp b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/cpp-calls-c/main.cpp
new file mode 100644
index 00000000..1c17429d
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/cpp-calls-c/main.cpp
@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <iostream>
+#include "ops.h"
+
+int main(void)
+{
+	std::cout << "add(10, 3): " << add(10, 3) << std::endl;
+	std::cout << "sub(10, 3): " << sub(10, 3) << std::endl;
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/cpp-calls-c/ops.h b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/cpp-calls-c/ops.h
new file mode 100644
index 00000000..f1ce5712
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/cpp-calls-c/ops.h
@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef OPS_H_
+#define OPS_H_		1
+
+int add(int a, int b);
+int sub(int a, int b);
+
+#endif
diff --git a/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/cpp-calls-c/sub.c b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/cpp-calls-c/sub.c
new file mode 100644
index 00000000..ecde8e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/bad/cpp-calls-c/sub.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int sub(int a, int b)
+{
+	return a - b;
+}
diff --git a/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/c-calls-cpp/.gitignore b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/c-calls-cpp/.gitignore
new file mode 100644
index 00000000..95811e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/c-calls-cpp/.gitignore
@@ -0,0 +1 @@
+/main
diff --git a/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/c-calls-cpp/Makefile b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/c-calls-cpp/Makefile
new file mode 100644
index 00000000..63092931
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/c-calls-cpp/Makefile
@@ -0,0 +1,22 @@
+CFLAGS = -Wall -g
+CXXFLAGS = -Wall -g
+LDFLAGS = -lstdc++
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: main
+
+main: main.o add.o sub.o
+	$(CC) $(LDFLAGS) -o $@ $^
+
+main.o: main.c ops.h
+
+add.o: add.cpp
+
+sub.o: sub.cpp
+
+clean:
+	-rm -f main main.o add.o sub.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/c-calls-cpp/add.cpp b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/c-calls-cpp/add.cpp
new file mode 100644
index 00000000..442f6261
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/c-calls-cpp/add.cpp
@@ -0,0 +1,8 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include "ops.h"
+
+int add(int a, int b)
+{
+	return a + b;
+}
diff --git a/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/c-calls-cpp/main.c b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/c-calls-cpp/main.c
new file mode 100644
index 00000000..77b52aa2
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/c-calls-cpp/main.c
@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <stdio.h>
+#include "ops.h"
+
+int main(void)
+{
+	printf("add(10, 3): %d\n", add(10, 3));
+	printf("sub(10, 3): %d\n", sub(10, 3));
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/c-calls-cpp/ops.h b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/c-calls-cpp/ops.h
new file mode 100644
index 00000000..491ddcb9
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/c-calls-cpp/ops.h
@@ -0,0 +1,17 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef OPS_H_
+#define OPS_H_		1
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+int add(int a, int b);
+int sub(int a, int b);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/c-calls-cpp/sub.cpp b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/c-calls-cpp/sub.cpp
new file mode 100644
index 00000000..7f8243b7
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/c-calls-cpp/sub.cpp
@@ -0,0 +1,8 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include "ops.h"
+
+int sub(int a, int b)
+{
+	return a - b;
+}
diff --git a/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/cpp-calls-c/.gitignore b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/cpp-calls-c/.gitignore
new file mode 100644
index 00000000..95811e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/cpp-calls-c/.gitignore
@@ -0,0 +1 @@
+/main
diff --git a/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/cpp-calls-c/Makefile b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/cpp-calls-c/Makefile
new file mode 100644
index 00000000..faa510b3
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/cpp-calls-c/Makefile
@@ -0,0 +1,21 @@
+CFLAGS = -Wall -g
+CXXFLAGS = -Wall -g
+
+.DEFAULT_GOAL: all
+
+.PHONY: all clean
+
+all: main
+
+main: main.o add.o sub.o
+	$(CXX) $(LDFLAGS) -o $@ $^
+
+main.o: main.cpp ops.h
+
+add.o: add.c
+
+sub.o: sub.c
+
+clean:
+	-rm -f main main.o add.o sub.o
+	-rm -f *~
diff --git a/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/cpp-calls-c/add.c b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/cpp-calls-c/add.c
new file mode 100644
index 00000000..36db038f
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/cpp-calls-c/add.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int add(int a, int b)
+{
+	return a + b;
+}
diff --git a/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/cpp-calls-c/main.cpp b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/cpp-calls-c/main.cpp
new file mode 100644
index 00000000..1c17429d
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/cpp-calls-c/main.cpp
@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <iostream>
+#include "ops.h"
+
+int main(void)
+{
+	std::cout << "add(10, 3): " << add(10, 3) << std::endl;
+	std::cout << "sub(10, 3): " << sub(10, 3) << std::endl;
+
+	return 0;
+}
diff --git a/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/cpp-calls-c/ops.h b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/cpp-calls-c/ops.h
new file mode 100644
index 00000000..491ddcb9
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/cpp-calls-c/ops.h
@@ -0,0 +1,17 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef OPS_H_
+#define OPS_H_		1
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+int add(int a, int b);
+int sub(int a, int b);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/cpp-calls-c/sub.c b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/cpp-calls-c/sub.c
new file mode 100644
index 00000000..ecde8e00
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/guides/cpp-obs/support/good/cpp-calls-c/sub.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+int sub(int a, int b)
+{
+	return a - b;
+}
diff --git a/chapters/hardware-software-interface/linking/reading/README.md b/chapters/hardware-software-interface/linking/reading/README.md
new file mode 100644
index 00000000..de09951c
--- /dev/null
+++ b/chapters/hardware-software-interface/linking/reading/README.md
@@ -0,0 +1,225 @@
+# Linking
+
+Linking is the final phase of the building process.
+Linking combines multiple object files into an executable file.
+
+To obtain an executable file from object files, the linker performs the following actions:
+
+1. Symbol resolution: locating the undefined symbols of one object file in other object files.
+1. Section merging: merging sections of the same type from different object files into a single section in the executable file.
+1. Address binding: after merging, the effective address symbols within the executable file can be established.
+1. Symbol relocation: once the symbol addresses are set, the instructions and data referring to those addresses in the executable must be updated.
+1. Entry point establishment: specifying the address of the first instruction to be executed.
+
+## Linker Invocation
+
+The linker is generally invoked by the compilation utility (`gcc`, `clang`, `cl`).
+Thus, invoking the linker is transparent to the user.
+In specific cases, such as creating a kernel image or images for embedded systems, the user will invoke the linker directly.
+
+If we have a source C file `app.c`, we will use the compiler to obtain the object file `app.o`:
+
+```console
+gcc -c -o app.o app.c
+```
+
+Then, to obtain the executable file `app` from the object file `app.o`, we use the `gcc` utility again:
+
+```console
+gcc -o app app.o
+```
+
+In the background, `gcc` will invoke the linker and build the executable `app`.
+The linker will also link against the standard C library (libc).
+
+The linking process will work only if the file `app.c` has the `main()` function defined, which is the main function of the program.
+Linked files must have a single `main()` function in order to produce an executable.
+
+If we have multiple C source files, we invoke the compiler for each file and then the linker:
+
+```console
+gcc -c -o helpers.o helpers.c
+gcc -c -o app.o app.c
+gcc -o app app.o helpers.o
+```
+
+The last command is the linking command, which links the object files `app.o` and `helpers.o` into the executable file `app`.
+
+In the case of C++ source files, we will use the `g++` command:
+
+```console
+g++ -c -o helpers.o helpers.cpp
+g++ -c -o app.o app.cpp
+g++ -o app app.o helpers.o
+```
+
+We can also use the `gcc` command for linking, specifying linking with the standard C++ library (libc++):
+
+```console
+gcc -o app app.o helpers.o -lstdc++
+```
+
+The Linux linking utility, `ld`, is invoked transparently by `gcc` or `g++`.
+To see how the linker is invoked, we use the `-v` option of the `gcc` utility, with the following output:
+
+```console
+/usr/lib/gcc/x86_64-linux-gnu/7/collect2 -plugin /usr/lib/gcc/x86_64-linux-gnu/7/liblto_plugin.so
+-plugin-opt=/usr/lib/gcc/x86_64-linux-gnu/7/lto-wrapper -plugin-opt=-fresolution=/tmp/ccwnf5NM.res
+-plugin-opt=-pass-through=-lgcc -plugin-opt=-pass-through=-lgcc_s -plugin-opt=-pass-through=-lc
+-plugin-opt=-pass-through=-lgcc -plugin-opt=-pass-through=-lgcc_s --build-id --eh-frame-hdr -m elf_i386 --hash-style=gnu
+--as-needed -dynamic-linker /lib/ld-linux.so.2 -z relro -o hello
+/usr/lib/gcc/x86_64-linux-gnu/7/../../../i386-linux-gnu/crt1.o
+/usr/lib/gcc/x86_64-linux-gnu/7/../../../i386-linux-gnu/crti.o /usr/lib/gcc/x86_64-linux-gnu/7/32/crtbegin.o
+-L/usr/lib/gcc/x86_64-linux-gnu/7/32 -L/usr/lib/gcc/x86_64-linux-gnu/7/../../../i386-linux-gnu
+-L/usr/lib/gcc/x86_64-linux-gnu/7/../../../../lib32 -L/lib/i386-linux-gnu -L/lib/../lib32 -L/usr/lib/i386-linux-gnu
+-L/usr/lib/../lib32 -L/usr/lib/gcc/x86_64-linux-gnu/7 -L/usr/lib/gcc/x86_64-linux-gnu/7/../../../i386-linux-gnu
+-L/usr/lib/gcc/x86_64-linux-gnu/7/../../.. -L/lib/i386-linux-gnu -L/usr/lib/i386-linux-gnu hello.o -lgcc --push-state
+--as-needed -lgcc_s --pop-state -lc -lgcc --push-state --as-needed -lgcc_s --pop-state
+/usr/lib/gcc/x86_64-linux-gnu/7/32/crtend.o /usr/lib/gcc/x86_64-linux-gnu/7/../../../i386-linux-gnu/crtn.o
+COLLECT_GCC_OPTIONS='-no-pie' '-m32' '-v' '-o' 'hello' '-mtune=generic' '-march=i686'
+```
+
+The `collect2` utility is, in fact, a wrapper around the `ld` utility.
+The result of running the command is complex. A "manual" invocation of the `ld` command would look like this:
+
+```console
+ld -dynamic-linker /lib/ld-linux.so.2 -m elf_i386 -o app /usr/lib32/crt1.o /usr/lib32/crti.o app.o helpers.o -lc /usr/lib32/crtn.o
+```
+
+The arguments of the above command have the following meanings:
+
+- `-dynamic-linker /lib/ld-linux.so.2`: specifies the dynamic loader/linker used for loading the dynamic executable
+- `-m elf_i386`: links files for the x86 architecture (32-bit, i386)
+- `/usr/lib32/crt1.o`, `/usr/lib32/crti.o`, `/usr/lib32/crtn.o`: represent the C runtime library (`crt` - *C runtime*) that provides the necessary support for loading the executable
+- `-lc`: links against standard C library (libc)
+
+## File Inspection
+
+To track the linking process, we use static analysis utilities such as `nm`, `objdump`, and `readelf`.
+
+We use the `nm` utility to display symbols from an object file or an executable file:
+
+```console
+$ nm hello.o
+00000000 T main
+         U puts
+
+$ nm hello
+0804a01c B __bss_start
+0804a01c b completed.7283
+0804a014 D __data_start
+0804a014 W data_start
+08048370 t deregister_tm_clones
+08048350 T _dl_relocate_static_pie
+080483f0 t __do_global_dtors_aux
+08049f10 t __do_global_dtors_aux_fini_array_entry
+0804a018 D __dso_handle
+08049f14 d _DYNAMIC
+0804a01c D _edata
+0804a020 B _end
+080484c4 T _fini
+080484d8 R _fp_hw
+08048420 t frame_dummy
+08049f0c t __frame_dummy_init_array_entry
+0804861c r __FRAME_END__
+0804a000 d _GLOBAL_OFFSET_TABLE_
+         w __gmon_start__
+080484f0 r __GNU_EH_FRAME_HDR
+080482a8 T _init
+08049f10 t __init_array_end
+08049f0c t __init_array_start
+080484dc R _IO_stdin_used
+080484c0 T __libc_csu_fini
+08048460 T __libc_csu_init
+         U __libc_start_main@@GLIBC_2.0
+08048426 T main
+         U puts@@GLIBC_2.0
+080483b0 t register_tm_clones
+08048310 T _start
+0804a01c D __TMC_END__
+08048360 T __x86.get_pc_thunk.bx
+```
+
+The `nm` command displays three columns:
+
+- the symbol's address
+- the section and type where the symbol is located
+- the symbol's name
+
+A symbol is the name of a global variable or function.
+It is used by the linker to make connections between different object modules.
+Symbols are not necessary for executables, which is why executables can be stripped.
+
+The symbol's address is actually the offset within a section for object files and is the effective address for executables.
+
+The second column specifies the section and type of the symbol.
+If it is uppercase, then the symbol is exported and can be used by another module.
+If it is lowercase, then the symbol is not exported and is local to the object module, making it unusable in other modules.
+Thus:
+
+- `d`: the symbol is in the initialized data area (`.data`), unexported
+- `D`: the symbol is in the initialized data area (`.data`), exported
+- `t`: the symbol is in the code area (`.text`), unexported
+- `T`: the symbol is in the code area (`.text`), exported
+- `r`: the symbol is in the read-only data area (`.rodata`), unexported
+- `R`: the symbol is in the read-only data area (`.rodata`), exported
+- `b`: the symbol is in the uninitialized data area (`.bss`), unexported
+- `B`: the symbol is in the uninitialized data area (`.bss`), exported
+- `U`: the symbol is undefined (it is used in the current module but defined in another module)
+
+More information can be found in the manual page for the `nm` utility.
+
+Using the `objdump` command, we can disassemble the code of object files and executables.
+This way, we can see the assembly code and how the modules operate.
+
+The `readelf` command is used to inspect object or executable files.
+With the `readelf` command, we can view the headers of files.
+An important piece of information in the header of executable files is the entry point, the address of the first instruction executed:
+
+```console
+$ readelf -h hello
+ELF Header:
+  Magic:   7f 45 4c 46 01 01 01 00 00 00 00 00 00 00 00 00
+  Class:                             ELF32
+  Data:                              2's complement, little endian
+  Version:                           1 (current)
+  OS/ABI:                            UNIX - System V
+  ABI Version:                       0
+  Type:                              EXEC (Executable file)
+  Machine:                           Intel 80386
+  Version:                           0x1
+  Entry point address:               0x8048310
+  Start of program headers:          52 (bytes into file)
+  Start of section headers:          8076 (bytes into file)
+  Flags:                             0x0
+  Size of this header:               52 (bytes)
+  Size of program headers:           32 (bytes)
+  Number of program headers:         9
+  Size of section headers:           40 (bytes)
+  Number of section headers:         35
+  Section header string table index: 34
+```
+
+Using the `readelf` command, we can see the sections of an executable/object file:
+
+```console
+$ readelf -S hello
+There are 35 section headers, starting at offset 0x1f8c:
+Section Headers:
+  [Nr] Name              Type            Addr     Off    Size   ES Flg Lk Inf Al
+  [ 0]                   NULL            00000000 000000 000000 00      0   0  0
+  [ 1] .interp           PROGBITS        08048154 000154 000013 00   A  0   0  1
+  [ 2] .note.ABI-tag     NOTE            08048168 000168 000020 00   A  0   0  4
+  [ 3] .note.gnu.build-i NOTE            08048188 000188 000024 00   A  0   0  4
+[...]
+```
+
+Also, with the `readelf` command, we can list (dump) the contents of a specific section:
+
+```console
+$ readelf -x .rodata hello
+
+Hex dump of section '.rodata':
+  0x080484d8 03000000 01000200 48656c6c 6f2c2057 ........Hello, W
+  0x080484e8 6f726c64 2100                       orld!.
+```
diff --git a/config.yaml b/config.yaml
index 9300ecec..47fca53c 100644
--- a/config.yaml
+++ b/config.yaml
@@ -261,6 +261,26 @@ docusaurus:
                               - Overflow in C/: overflow-in-c/
                               - Overwrite Return Address/: overwrite-ret-addr/
                               - Overflow for Binary File/: overflow-for-binary/
+      - Lab 12 - Linking:
+          path: chapters/hardware-software-interface/linking/
+          subsections:
+            - Reading/: reading/
+            - Drills:
+                path: drills/
+                subsections:
+                  - Tasks:
+                      path: tasks/
+                      subsections:
+                        - Single File Linking/: single-link/
+                        - Multiple File Linking/: multiple-link/
+                        - Entry Point Fixing 1/: entry-fix-1/
+                        - Entry Point Fixing 2/: entry-fix-2/
+                        - Warning Resolution/: include-fix/
+                        - Export Resolution/: export-fix/
+                        - Linking with Symbols/: var-func-fix/
+                        - Library Issues Resolution/: lib-fix/
+                        - Linking an Object File/: obj-link-dev/
+
     # static_assets:
     #   - template-chapter-template-topic: /build/make_assets/chapters/template-chapter/template-topic/slides/_site
     config_meta: