# stargazing this repository contains experiments in building third-party software against [cosmopolitan libc.](https://justine.lol/cosmopolitan/) the provided scripts produce APEs (Actually Portable Executables) that run on Linux, Mac, Windows, FreeBSD, OpenBSD, and NetBSD. **however,** despite *running* on all platforms, not every feature is available on every platform. cosmopolitan already does a tremendous job at polyfilling missing features across platforms, but pre-existing software still takes a lot of tweaking to before becoming fully functional. ## notes ### Docker this project uses [Dockerfiles][df] to allow for *mostly-reproducible* builds. [podman][podman is used] instead of docker, because the official docker software is commercial and obnoxious. **neither docker nor podman is required for executing the binaries.** binaries are to be isolated and extracted from the resulting containers. those binaries can then be transferred across platforms, like any other APE. [df]: https://docs.docker.com/engine/reference/builder/ [podman]: https://docs.podman.io/en/latest/markdown/podman-build.1.html in the future, it would be nice to use something like [what Void Linux does for its packages,][void] which would entirely sidestep the clunkiness of Dockerfiles and working with containers. [void]: https://github.com/void-linux/void-packages make no mistake, this project does *not* strive for reproducible builds [in any way that nix does.](https://nixos.org/guides/how-nix-works.html) ### Host OS this project must be built on a host running Linux. if you are not running Linux, use a VM of some sort. i personally use VirtualBox running Alpine Linux. i have not tried building with WSL2. ### Code Style this project encourages a heretical and horrifying style of code for its shell scripts. the intent is to chain `&&`s while facilitating trivial re-ordering of lines. for instance, a `RUN` command in a Dockerfile (which just executes a line of shell) might look like this: ```sh RUN : \ && echo hello \ && note() \ { : \ && printf '\033[1m%s\033[m: %s\n' >&2 \ noted "$*" \ ;} \ && note '\\( o _ o )//' \ ; ``` #### gratuitous explanation * 4-space indentation is a must, since at least three characters are needed to contain the operators on the left of each line. * `:` is akin to the `true` command; it's used as a no-op that only sets the most recent exit code (`$?`) to `0`. * `\` continues the shell command to the next line; the proceeding newline is removed and ignored. * `&&` is a short-circuiting operator that only evaluates its right-hand side when `$?` is `0`. `&&` is preferred over a simple semicolon because most programs use a non-zero exit code to indicate that an error occurred, whereas `;` will continue executing code, even in the presence of an error. **note:** the `diff` command breaks the convention and uses both `0` and `1` as normal exit codes. * `||` is like `&&` but only executes when `$?` is *not* `0`. **important:** `||` has a lower precedence than `&&`! make sure to wrap your `||`s in braces unless you want to capture *everything* before it. for example, an excerpt of a shell script might look like this: ` && { test -e myfile || touch myfile ;} \` * leftmost `&&`s and `||`s are always centered within their 4-space indent. * avoid using pipes (`|`) when possible, because only the exit code of the final command in any pipe is respected. instead, write intermediate data to `/tmp` when possible. remember to mount `/tmp` as a `tmpfs` at the start of the `RUN` command! * functions are declared (`()`) on their own line without any braces or other commands. * `{ :` is used to begin a multi-line block, similar to how `RUN :` begins a shell command. sadly, the space between the brace and the colon is not optional. * `;}` is used to finish a multi-line block. this is aligned with the preceeding `&&` and `||` operators. thankfully, the space between `;` and `}` is optional. * a final `;` is used to finish off the line-continutation. this means that every line before it can end with a `\`, which simplifies editing. when podman gives you strange errors, double-check that you aren't forgetting a `\` or the final semicolon. * redirections are usually specified *before* a final list of arguments. this makes skimming code easier when arguments extend across many lines. * **TODO:** explain `if cmd \␤ ;then : \␤ && cmd \␤ ;fi`. * **TODO:** explain `for cmd \␤ ;do : \␤ && cmd \␤ ;done`. * **TODO:** explain `while cmd \␤ ;do : \␤ && cmd \␤ ;done`. * **TODO:** explain `test`s.