This patch fixes SLiM so it really waits for the X server to be ready
before attempting to connect to it.  Indeed, the X server notices that
its parent process has a handler for SIGUSR1, and consequently sends it
SIGUSR1 when it's ready to accept connections.

The problem was that SLiM doesn't pay attention to SIGUSR1.  So in practice,
if X starts slowly, then SLiM gets ECONNREFUSED a couple of time on
/tmp/.X11-unix/X0, then goes on trying to connect to localhost:6000,
where nobody answers; eventually, it times out and tries again on
/tmp/.X11-unix/X0, and finally it shows up on the screen.

Patch by L. Courtès.

--- slim-1.3.6/app.cpp	2014-02-05 15:27:20.000000000 +0100
+++ slim-1.3.6/app.cpp	2014-02-09 22:42:04.000000000 +0100
@@ -119,7 +119,9 @@ void CatchSignal(int sig) {
 	exit(ERR_EXIT);
 }
 
+static volatile int got_sigusr1 = 0;
 void User1Signal(int sig) {
+	got_sigusr1 = 1;
 	signal(sig, User1Signal);
 }
 
@@ -884,6 +886,7 @@ int App::WaitForServer() {
 	int	ncycles	 = 120;
 	int	cycles;
 
+	while (!got_sigusr1);
 	for(cycles = 0; cycles < ncycles; cycles++) {
 		if((Dpy = XOpenDisplay(DisplayName))) {
 			XSetIOErrorHandler(xioerror);
7f'>refs</a><a class='active' href='/guix/log/gnu/packages/file.scm'>log</a><a href='/guix/tree/gnu/packages/file.scm?id=db622bb7166c70a1c2d00996c2577b0e1d83f47f'>tree</a><a href='/guix/commit/gnu/packages/file.scm?id=db622bb7166c70a1c2d00996c2577b0e1d83f47f'>commit</a><a href='/guix/diff/gnu/packages/file.scm?id=db622bb7166c70a1c2d00996c2577b0e1d83f47f'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/gnu/packages/file.scm'>
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<div class='path'>path: <a href='/guix/log/?id=db622bb7166c70a1c2d00996c2577b0e1d83f47f'>root</a>/<a href='/guix/log/gnu?id=db622bb7166c70a1c2d00996c2577b0e1d83f47f'>gnu</a>/<a href='/guix/log/gnu/packages?id=db622bb7166c70a1c2d00996c2577b0e1d83f47f'>packages</a>/<a href='/guix/log/gnu/packages/file.scm?id=db622bb7166c70a1c2d00996c2577b0e1d83f47f'>file.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/gnu/packages/file.scm?id=db622bb7166c70a1c2d00996c2577b0e1d83f47f&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2023-01-31 10:15:57 +0200'>2023-01-31</span></td><td><a href='/guix/commit/gnu/packages/file.scm?id=70b7d19ecf35ec27b169ea1ccc772d4a9ff7df93'>gnu: file: Update to 5.44.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/file.scm (file): Update to 5.44.
</span></span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2022-11-14 18:44:07 +0200'>2022-11-14</span></td><td><a href='/guix/commit/gnu/packages/file.scm?id=f1316ff7bf6d5d69ba7295435803a9e320b62813'>gnu: file: Update to 5.43.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/file.scm (file): Update to 5.43.
</span></span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2022-06-14 20:58:20 +0300'>2022-06-14</span></td><td><a href='/guix/commit/gnu/packages/file.scm?id=04c716afa56de3b8ff2b4e98673ddd4544720914'>gnu: file: Update to 5.42.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/file.scm (file): Update to 5.42.
[source]: Update source URI.
[properties]: Remove field.
</span></span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2022-01-27 17:01:20 +0200'>2022-01-27</span></td><td><a href='/guix/commit/gnu/packages/file.scm?id=6ac6a7e0202e536b42756413d464f98e0c02f5c1'>gnu: file: Update to 5.41.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/file.scm (file): Absorb file-next.
* gnu/packages/commencement.scm (file-boot0)[arguments]: Add make-flag
to set CFLAGS.
* gnu/packages/diffoscope.scm (diffoscope): Remove file-next.
* gnu/packages/python-xyz.scm (python-magic)[inputs]: Replace file-next
with file.
</span></span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2021-12-16 22:21:13 +0100'>2021-12-16</span></td><td><a href='/guix/commit/gnu/packages/file.scm?id=12c75628b4322853943ae0d0a833e371c02b97f4'>gnu: file: Add 5.41.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/file.scm (file-next): New variable.
</span></span></td><td>Marius Bakke</td></tr>
<tr><td><span title='2021-10-12 17:46:23 +0000'>2021-10-12</span></td><td><a href='/guix/commit/gnu/packages/file.scm?id=a1eca979fb8da842e73c42f4f53be29b169810f2'>Merge remote-tracking branch 'origin/master' into core-updates-frozen.</a></td><td>Mathieu Othacehe</td></tr>
<tr><td><span title='2021-09-25 09:34:29 +0200'>2021-09-25</span></td><td><a href='/guix/commit/gnu/packages/file.scm?id=a5b2474037d749f42a816c60f0393941ba97444e'>gnu: Consolidate duplicate copyright names.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/android.scm: Consolidate copyright lines with the same email address.
* gnu/packages/code.scm: Likewise.
* gnu/packages/cpp.scm: Likewise.
* gnu/packages/databases.scm: Likewise.
* gnu/packages/emacs-xyz.scm: Likewise.
* gnu/packages/file.scm: Likewise.
* gnu/packages/freedesktop.scm: Likewise.
* gnu/packages/gl.scm: Likewise.
* gnu/packages/gps.scm: Likewise.
* gnu/packages/linux.scm: Likewise.
* gnu/packages/networking.scm: Likewise.
* gnu/packages/python-xyz.scm: Likewise.
* gnu/packages/python.scm: Likewise.
* gnu/packages/video.scm: Likewise.
* gnu/packages/xdisorg.scm: Likewise.
* gnu/services/web.scm: Likewise.

Signed-off-by: Liliana Marie Prikler &lt;liliana.prikler@gmail.com&gt;
</span></span></td><td>Greg Hogan</td></tr>
<tr><td><span title='2021-04-16 14:39:48 +0300'>2021-04-16</span></td><td><a href='/guix/commit/gnu/packages/file.scm?id=fcc39864dba82e14895afbe841091091366c96bc'>Merge remote-tracking branch 'origin/master' into core-updates</a><span class='msg-avail'>...<span class='msg-tooltip'> Conflicts:
	gnu/local.mk
	gnu/packages/boost.scm
	gnu/packages/chez.scm
	gnu/packages/compression.scm
	gnu/packages/crates-io.scm
	gnu/packages/docbook.scm
	gnu/packages/engineering.scm
	gnu/packages/gcc.scm
	gnu/packages/gl.scm
	gnu/packages/gtk.scm
	gnu/packages/nettle.scm
	gnu/packages/python-check.scm
	gnu/packages/python-xyz.scm
	gnu/packages/radio.scm
	gnu/packages/rust.scm
	gnu/packages/sqlite.scm
	guix/build-system/node.scm
</span></span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2021-04-05 12:03:08 +0200'>2021-04-05</span></td><td><a href='/guix/commit/gnu/packages/file.scm?id=51fa1b6ea5255b3b9112d0c9c86814019955a2a7'>gnu: file: Add 'release-monitoring-url' property.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/file.scm (file)[properties]: New field.
</span></span></td><td>Ludovic Courtès</td></tr>