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='2021-03-24 14:29:39 +0200'>2021-03-24</span></td><td><a href='/guix/commit/gnu/packages/ccache.scm?id=3f944e62044e7afd35b03f06525f04157f05f05d'>gnu: ccache: Update to 4.2.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/ccache.scm (ccache): Update to 4.2.
[build-system]: Switch to cmake-build-system.
[inputs]: Add zstd:lib.
[arguments]: Move substitution before change of directory and add phase
to set HOME variable.

Signed-off-by: Efraim Flashner &lt;efraim@flashner.co.il&gt;
</span></span></td><td>Greg Hogan</td></tr>
<tr><td><span title='2020-10-03 00:22:59 +0200'>2020-10-03</span></td><td><a href='/guix/commit/gnu/packages/ccache.scm?id=2259eeec8014697da33b559f46f74965410e1a31'>gnu: ccache: Update to 3.7.12.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/ccache.scm (ccache): Update to 3.7.12.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2020-07-23 16:25:11 +0200'>2020-07-23</span></td><td><a href='/guix/commit/gnu/packages/ccache.scm?id=e4d341fa74d005cc3cd1437a1908ba1993d54d5b'>gnu: ccache: Update to 3.7.11.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/ccache.scm (ccache): Update to 3.7.11.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2020-06-29 15:47:12 +0200'>2020-06-29</span></td><td><a href='/guix/commit/gnu/packages/ccache.scm?id=17154ad99f399058912a86def3081377acdc79e3'>gnu: ccache: Update to 3.7.10.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/ccache.scm (ccache): Update to 3.7.10.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2020-05-30 16:54:50 +0200'>2020-05-30</span></td><td><a href='/guix/commit/gnu/packages/ccache.scm?id=a29a8a91fda99c5bba996b80707b8d42f2aa5080'>gnu: ccache: Update to 3.7.9.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/ccache.scm (ccache): Update to 3.7.9.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2020-03-07 22:30:06 +0100'>2020-03-07</span></td><td><a href='/guix/commit/gnu/packages/ccache.scm?id=74ff08e6b8a0f0f53c89fb25faa31c597ad92f48'>gnu: ccache: Fix indentation</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/ccache.scm (ccache): Fix indentation

Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Vincent Legoll</td></tr>
<tr><td><span title='2020-03-07 22:30:06 +0100'>2020-03-07</span></td><td><a href='/guix/commit/gnu/packages/ccache.scm?id=9eb456b8c7ec28e794b8774a68ced32935998e32'>gnu: ccache: Update to 3.7.7.</a><span class='msg-avail'>...<span class='msg-tooltip'>gnu/packages/ccache.scm (ccache): Update to 3.7.7, update homepage
to ccache.dev, get source code from github, remove fortran 77 from
description.

Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Vincent Legoll</td></tr>
<tr><td><span title='2019-08-22 00:25:40 +0200'>2019-08-22</span></td><td><a href='/guix/commit/gnu/packages/ccache.scm?id=3251c628f754eaceaa0515fadffcf8e64e1ca66e'>gnu: ccache: Update to 3.6.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/ccache.scm (ccache): Update to 3.6.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>