doc: rewrite installShellFiles

doc/hooks/installShellFiles.section.md

@@ -1,16 +1,79 @@
 # `installShellFiles` {#installshellfiles}
 
-This hook helps with installing manpages and shell completion files. It exposes 2 shell functions `installManPage` and `installShellCompletion` that can be used from your `postInstall` hook.
+This hook adds helpers that install artifacts like executable files, manpages
+and shell completions.
 
-The `installManPage` function takes one or more paths to manpages to install. The manpages must have a section suffix, and may optionally be compressed (with `.gz` suffix). This function will place them into the correct `share/man/man<section>/` directory, in [`outputMan`](#outputman).
+It exposes the following functions that can be used from your `postInstall`
+hook:
 
-The `installShellCompletion` function takes one or more paths to shell completion files. By default it will autodetect the shell type from the completion file extension, but you may also specify it by passing one of `--bash`, `--fish`, or `--zsh`. These flags apply to all paths listed after them (up until another shell flag is given). Each path may also have a custom installation name provided by providing a flag `--name NAME` before the path. If this flag is not provided, zsh completions will be renamed automatically such that `foobar.zsh` becomes `_foobar`. A root name may be provided for all paths using the flag `--cmd NAME`; this synthesizes the appropriate name depending on the shell (e.g. `--cmd foo` will synthesize the name `foo.bash` for bash and `_foo` for zsh).
+## `installBin` {#installshellfiles-installbin}
+
+The `installBin` function takes one or more paths to files to install as
+executable files.
+
+This function will place them into [`outputBin`](#outputbin).
+
+### Example Usage {#installshellfiles-installbin-exampleusage}
+
+```nix
+{
+  nativeBuildInputs = [ installShellFiles ];
+
+  # Sometimes the file has an undersirable name. It should be renamed before
+  # being installed via installBin
+  postInstall = ''
+    mv a.out delmar
+    installBin foobar delmar
+  '';
+}
+```
+
+## `installManPage` {#installshellfiles-installmanpage}
+
+The `installManPage` function takes one or more paths to manpages to install.
+
+The manpages must have a section suffix, and may optionally be compressed (with
+`.gz` suffix). This function will place them into the correct
+`share/man/man<section>/` directory in [`outputMan`](#outputman).
+
+### Example Usage {#installshellfiles-installmanpage-exampleusage}
+
+```nix
+{
+  nativeBuildInputs = [ installShellFiles ];
+
+  # Sometimes the manpage file has an undersirable name; e.g. it conflicts with
+  # another software with an equal name. It should be renamed before being
+  # installed via installManPage
+  postInstall = ''
+    mv fromsea.3 delmar.3
+    installManPage foobar.1 delmar.3
+  '';
+}
+```
+
+## `installShellCompletion` {#installshellfiles-installshellcompletion}
+
+The `installShellCompletion` function takes one or more paths to shell
+completion files.
+
+By default it will autodetect the shell type from the completion file extension,
+but you may also specify it by passing one of `--bash`, `--fish`, or
+`--zsh`. These flags apply to all paths listed after them (up until another
+shell flag is given). Each path may also have a custom installation name
+provided by providing a flag `--name NAME` before the path. If this flag is not
+provided, zsh completions will be renamed automatically such that `foobar.zsh`
+becomes `_foobar`. A root name may be provided for all paths using the flag
+`--cmd NAME`; this synthesizes the appropriate name depending on the shell
+(e.g. `--cmd foo` will synthesize the name `foo.bash` for bash and `_foo` for
+zsh).
+
+### Example Usage {#installshellfiles-installshellcompletion-exampleusage}
 
 ```nix
 {
   nativeBuildInputs = [ installShellFiles ];
   postInstall = ''
-    installManPage doc/foobar.1 doc/barfoo.3
     # explicit behavior
     installShellCompletion --bash --name foobar.bash share/completions.bash
     installShellCompletion --fish --name foobar.fish share/completions.fish
@@ -21,9 +84,17 @@ The `installShellCompletion` function takes one or more paths to shell completio
 }
 ```
 
-The path may also be a fifo or named fd (such as produced by `<(cmd)`), in which case the shell and name must be provided (see below).
+The path may also be a fifo or named fd (such as produced by `<(cmd)`), in which
+case the shell and name must be provided (see below).
 
-If the destination shell completion file is not actually present or consists of zero bytes after calling `installShellCompletion` this is treated as a build failure. In particular, if completion files are not vendored but are generated by running an executable, this is likely to fail in cross compilation scenarios. The result will be a zero byte completion file and hence a build failure. To prevent this, guard the completion commands against this, e.g.
+If the destination shell completion file is not actually present or consists of
+zero bytes after calling `installShellCompletion` this is treated as a build
+failure. In particular, if completion files are not vendored but are generated
+by running an executable, this is likely to fail in cross compilation
+scenarios. The result will be a zero byte completion file and hence a build
+failure. To prevent this, guard the completion generation commands.
+
+### Example Usage {#installshellfiles-installshellcompletion-exampleusage-guarded}
 
 ```nix
 {