Workaround for PATH_MAX usage on the Hurd.

Taken from https://salsa.debian.org/debian/screen/-/blob/master/debian/patches/61-default-PATH_MAX-if-undefined-for-hurd.patch

Description: Set PATH_MAX to 4096 if undefined
 Fixes FTBFS since 4.4.0 on GNU/Hurd. Updated to add one more occurrence for 4.5.0.
Author: Axel Beckert <abe@debian.org>
Bug: https://savannah.gnu.org/bugs/?50089
Last-Updated: 2017-01-18

--- a/tty.sh
+++ b/tty.sh
@@ -1478,6 +1478,13 @@
   return 0;
 }
 
+/*
+ * Define PATH_MAX to 4096 if it's not defined, like on GNU/Hurd
+ */
+
+#ifndef PATH_MAX
+#define PATH_MAX 4096
+#endif
 
 int CheckTtyname (char *tty)
 {
--- a/screen.h
+++ b/screen.h
@@ -109,6 +109,13 @@
 # define DEFAULT_BUFFERFILE	"/tmp/screen-exchange"
 #endif
 
+/*
+ * Define PATH_MAX to 4096 if it's not defined, like on GNU/Hurd
+ */
+
+#ifndef PATH_MAX
+#define PATH_MAX 4096
+#endif
 
 #if defined(hpux) && !(defined(VSUSP) && defined(VDSUSP) && defined(VWERASE) && defined(VLNEXT))
 # define HPUX_LTCHARS_HACK
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<tr><td><span title='2023-07-20 10:11:33 +0200'>2023-07-20</span></td><td><a href='/guix/commit/gnu/packages/adns.scm?id=bfcfe53c72f04e825f33269258c5ebbc33b70131'>gnu: c-ares: Skip failing tests on the Hurd.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/adns.scm (c-ares)[arguments: When building natively on the
Hurd, add phases 'skip-tests' and 'filter-hurd-tests'.
</span></span></td><td>Janneke Nieuwenhuizen</td></tr>
<tr><td><span title='2022-06-26 12:06:30 +0200'>2022-06-26</span></td><td><a href='/guix/commit/gnu/packages/adns.scm?id=7a0e57a81239b5e71e278c69db04e84185567210'>gnu: c-ares: Update to 1.18.1.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/adns.scm (c-ares): Update to 1.18.1.
</span></span></td><td>Marius Bakke</td></tr>
<tr><td><span title='2021-12-23 15:41:15 +0100'>2021-12-23</span></td><td><a href='/guix/commit/gnu/packages/adns.scm?id=94f8ba37cc3eff71809bd197378d075e33a9945c'>gnu: c-ares: Enable tests.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/adns.scm (c-ares)[arguments]: Enable tests.
</span></span></td><td>Jelle Licht</td></tr>
<tr><td><span title='2021-12-13 17:48:25 +0100'>2021-12-13</span></td><td><a href='/guix/commit/gnu/packages/adns.scm?id=8394619baceb118df92e355377fd543bb1aa501a'>gnu: Simplify package inputs.</a><span class='msg-avail'>...<span class='msg-tooltip'>This commit was obtained by running:

  ./pre-inst-env guix style

without any additional argument.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2021-11-17 23:43:14 +0100'>2021-11-17</span></td><td><a href='/guix/commit/gnu/packages/adns.scm?id=3a317f7476f8c6012e166ff9f340f861938721c9'>Merge branch 'master' into core-updates-frozen</a></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2021-11-15 22:43:23 +0100'>2021-11-15</span></td><td><a href='/guix/commit/gnu/packages/adns.scm?id=ecbf59abad4e146a80ea2849d12569886bce732e'>gnu: Add c-ares-for-node.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/adns.scm (c-ares-for-node): New variable.

Co-authored-by: Marius Bakke &lt;marius@gnu.org&gt;
</span></span></td><td>Jelle Licht</td></tr>
<tr><td><span title='2021-10-18 14:37:26 +0000'>2021-10-18</span></td><td><a href='/guix/commit/gnu/packages/adns.scm?id=e486b2b674badc80627b11077b7df2ac1cab92d8'>Merge remote-tracking branch 'signed/master' into core-updates</a></td><td>Mathieu Othacehe</td></tr>
<tr><td><span title='2021-10-17 02:27:16 +0200'>2021-10-17</span></td><td><a href='/guix/commit/gnu/packages/adns.scm?id=a1030d215197148aa0b86b75edccb70884c3769f'>gnu: c-ares: Update to 1.17.2.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/adns.scm (c-ares/fixed): Update to 1.17.2.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>