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);
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<div class='path'>path: <a href='/guix/log/?id=992d456421187b286d71bb0ca4fd698e17d343be'>root</a>/<a href='/guix/log/.dir-locals.el?id=992d456421187b286d71bb0ca4fd698e17d343be'>.dir-locals.el</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/.dir-locals.el?id=992d456421187b286d71bb0ca4fd698e17d343be&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2022-03-06 22:49:47 +0100'>2022-03-06</span></td><td><a href='/guix/commit/.dir-locals.el?id=a8d3033da61958c53c44dd5db90672bfc4533ef9'>import: github: Reuse HTTP connection for the /tags URL fallback.</a><span class='msg-avail'>...<span class='msg-tooltip'>* guix/import/github.scm (fetch-releases-or-tags): Call
'open-connection-for-uri' and reuse the same connection for the two
'http-fetch' calls.
* .dir-locals.el (scheme-mode): Add 'call-with-port'.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2022-03-06 22:49:46 +0100'>2022-03-06</span></td><td><a href='/guix/commit/.dir-locals.el?id=049aefddb2c88dd256a0705683a75704ff830b01'>tests: Add (guix http-client) tests.</a><span class='msg-avail'>...<span class='msg-tooltip'>* tests/http-client.scm: New file.
* Makefile.am (SCM_TESTS): Add it.
* .dir-locals.el (scheme-mode): Add 'with-http-server'.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2022-01-29 08:47:38 +0100'>2022-01-29</span></td><td><a href='/guix/commit/.dir-locals.el?id=69218e84f119c698a06febe030946f1eca571e2c'>.dir-locals.el: Don't mess up indentation of prepend and append.</a><span class='msg-avail'>...<span class='msg-tooltip'>The current version appears to assume special values in the first and second
package, but it's either all lists (default append) or all package input
expressions (inside modify-inputs), which themselves are either packages
or lists consisting of a package and a string.

* .dir-locals.el: Drop (eval . (put 'prepend 'scheme-indent-function 2))
and (eval . (put 'append 'scheme-indent-function 2)).
</span></span></td><td>Liliana Marie Prikler</td></tr>