From 26cfa224b7670f82d2f655541d0a9fca8e2eebc9 Mon Sep 17 00:00:00 2001
From: Tom Eichlersmith <31970302+tomeichlersmith@users.noreply.github.com>
Date: Mon, 6 May 2024 22:34:37 -0500
Subject: [PATCH] comments on support for OSs

---
 docs/src/getting_started.md | 53 +++++++++++++++++++++++++++++++++++++
 1 file changed, 53 insertions(+)

diff --git a/docs/src/getting_started.md b/docs/src/getting_started.md
index de0723b..e4e76ea 100644
--- a/docs/src/getting_started.md
+++ b/docs/src/getting_started.md
@@ -31,6 +31,59 @@ used to be the same project singularity before apptainer joined the Linux Founda
 fork of singularity now labeled singularityCE. So these two groupings also share tight similarities in 
 their command line interface making them natural groupings for denv.
 
+### Operating Systems
+_WARNING_: This section is laced with sarcasm.
+
+Containers are a technology created from combining a few Linux kernel features which makes them incredibly versatile
+and just confusing enough to be wrapped in thick layers of software and high-tech jargon. Many others have written about
+the technology underpinning containers[^2], so I won't go into more detail. I merely point this out to emphasize
+that non-Linux operating systems only access containers via Virtual Machines (VM) hosting Linux.[^3] Specifically, this
+means the other two big operating systems (Mircrosoft Windoze and Mac OS X) must be accomodated with VMs.
+
+#### Windoze
+Microsoft released Windoze Subsystem for Linux (WSL) in 2016 after finally realizing that work can only really get done
+within a functional operating system (like Linux-based ones). While largely expected to be apart of their
+[Embrace Extend Extinguish](https://en.wikipedia.org/wiki/Embrace,_extend,_and_extinguish) methodology, it still
+benefits us in that we can use containers in an almost equivalent way they would be used on a Linux system with
+the added step of having to wait for Windoze to boot before opening WSL. One of the most popular container
+runners docker [just plainly tells people to use WSL](https://docs.docker.com/desktop/install/windows-install/)
+when installing it.
+
+With this context in mind, **`denv` supports Windoze indirectly through WSL** in the same manner as docker.
+If you are on Windoze, first enable WSL and then interact with docker (or whatever runner you want) and `denv`
+within the WSL terminal.
+
+#### Mac OS X
+Both docker and podman support Mac OS X by spawning light weight VMs that can be kept idle while awaiting
+container instruction.[^4] Since Mac OS X has a more similar filesystem (and presumably kernel) to Linux,
+its VM is able to have a tighter integration with the host system. This has both benefits and difficulties.
+The benefit is that we presumably get performance improvements (I'm assuming this, I have not tested it.)
+The downside is that the user is not exposed directly to a terminal within the Linux kernel system like they
+are for Windoze (via WSL) or bare-metal Linux. This is an issue for `denv`
+(and [for other container wrappers](https://github.com/89luca89/distrobox/issues/36)) since, as a wrapper,
+we are trying to connect the container and host which is difficult to do when given only limited access
+to the intermediary VM layer.
+
+With this context in mind, **`denv` has limited support for Mac OS X**. Namely, `denv` is able to support
+_non-ID-necessary processes_ within the constructed denv. For example, compiling within `denv` works fine
+but making a commit with `git` within it does not. The discovery of this limitation and any ongoing work
+is tracked in [denv Issue #102](https://github.com/tomeichlersmith/denv/issues/102).
+
+[^2]: [The container is a lie](https://platform.sh/blog/the-container-is-a-lie/) is a nice article going into detail
+about the underpinnings of containers with a bit a click-baity title.Charliecloud's
+[containers are not special](https://hpc.github.io/charliecloud/tutorial.html#containers-are-not-special) 
+is only a moderate improvement in the title department and another approach to the material. Finally, I've liked
+[containers from scratch](https://ericchiang.github.io/post/containers-from-scratch/) which takes a more educational
+approach to help readers see why wrapping container creation and running in managers has been done (while also
+showing that it is an easy enough procedure for there to be many managers floating around).
+
+[^3]: _Technically_, I might be wrong here since a specific kernel might offer the same features that Linux
+offers that enables containers (or a specific subset of configurations of containers), but I digress.
+
+[^4]: I am not as familiar with the technical underpinnings of how docker or podman on Mac works since
+I have not had a computer to test and learn with it myself. If you have a technical correction to this
+section, please feel free to open an Issue or PR.
+
 ## Installation
 The most recent installation can be obtained by running the install script in the GitHub repository.
 ```shell