From 6a553f24439fe64fd3a2f0b5902f00590ca4241f Mon Sep 17 00:00:00 2001
From: Philip McGrath <philip@philipmcgrath.com>
Date: Thu, 4 Mar 2021 04:11:50 -0500
Subject: [PATCH] rktio: patch rktio_process for "/bin/sh" on Guix

Racket provides the functions `system` and `process`,
which execute shell commands using `sh` (or `cmd` on Windows).
Racket assumes that `sh` can be found at "/bin/sh",
which is not necessarily true on Guix.

This patch adds a special case for "/bin/sh" to `rktio_process`,
the C function that implements the core of `system`, `process`,
and related Racket functions.

If:

    1. The nonstandard but ubiquitous macro `_PATH_BSHELL` from
       <paths.h> is defined; and

    2. `rktio_process` is called with the exact path "/bin/sh"; and

    3. The file specified by `_PATH_BSHELL` exists;

then `rktio_process` will execute the file specified by `_PATH_BSHELL`
instead of "/bin/sh".

Checking that the path specified by `_PATH_BSHELL` exists safeguards
against obscure errors </td></tr></table>
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<div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/?id=3abaf0c4407b1f0e53f945bdbb13b6a8209c44dd&amp;ofs=50'>Collapse</a>)</th><th class='left'>Author</th></tr>
<tr class='logheader'><td><span title='2012-07-07 17:12:04 +0200'>2012-07-07</span></td><td class='logsubject'><a href='/guix/commit/?id=4fa697e932d5634441e4e281ce6879ca3a082a30'>utils: Change `substitute' and `substitute*' to work with several regexps.</a></td><td>Ludovic Courtès</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' class='logmsg'>
* guix/build/utils.scm (substitute): Change to accept a `pattern+procs'
  parameter.  Iterate over it.
  (substitute*): Adjust accordingly.

* distro/base.scm (guile-1.8): Adjust accordingly.


</td></tr>
<tr class='logheader'><td><span title='2012-07-07 16:51:13 +0200'>2012-07-07</span></td><td class='logsubject'><a href='/guix/commit/?id=03f9609ad9a8118b48bef7869e48c3afaae5f6ce'>distro: gawk: Disable parallel tests.</a></td><td>Ludovic Courtès</td></tr>
<tr class='nohover-highlight'><td/><td colspan='3' c