BigSurFix.md

This document explains how to solve the macOS Big Sur ESP32 compiling error

On a vanilla ESP32 board definition installation on mac OS Big Sur, the ESP32 throws the following (or similar) Python compiling error:

Traceback (most recent call last):
  File "esptool.py", line 57, in <module>
  File "/Library/Python/2.7/site-packages/PyInstaller/loader/pyimod03_importers.py", line 389, in load_module
  File "serial/tools/list_ports.py", line 29, in <module>
  File "/Library/Python/2.7/site-packages/PyInstaller/loader/pyimod03_importers.py", line 389, in load_module
  File "serial/tools/list_ports_posix.py", line 31, in <module>
  File "/Library/Python/2.7/site-packages/PyInstaller/loader/pyimod03_importers.py", line 389, in load_module
  File "serial/tools/list_ports_osx.py", line 32, in <module>
ValueError: dlsym(RTLD_DEFAULT, kIOMasterPortDefault): symbol not found
Failed to execute script esptool
exit status 255
Error compiling for board ESP32 Dev Module.

The original fix comes from here: https://forum.arduino.cc/index.php?topic=699989.0

I tried to make it a bit easier to understand. It was tested on the new Mac mini M1 with ARM chip, but it should work as well on Intel based systems.

1. Open Finder, select "Go to > Library" in dropdown menu (hidden folder, only visible, if "alt" is pressed

copy "esptool.py" from:

/Users/XXXXX/Library/Arduino15/packages/esp32/hardware/esp32/1.0.4/tools

to:

/Users/XXXXX/Library/Arduino15/packages/esp32/tools/esptool_py/2.6.1

2. Run the following commands in Terminal:

Enable superuser permissions (you need to enter your user password):

sudo su

Change directory:

cd /Users/XXXXX/Library/Arduino15/packages/esp32/tools/esptool_py/2.6.1

Set permissions:

chmod +x esptool.py

3. Back in finder, change the following in the file:

/Users/XXXXX/Library/Arduino15/packages/esp32/hardware/esp32/1.0.4/platform.txt

from:

tools.esptool_py.cmd=esptool

to:

tools.esptool_py.cmd=esptool.py

4. Safe the file, restart Arduino IDE

2021, TheDIYGuy999