Allow the configuration file and theme directory to be specified at run time.
Patch by Eelco Dolstra, from Nixpkgs.

--- slim-1.3.6/app.cpp	2013-10-02 00:38:05.000000000 +0200
+++ slim-1.3.6/app.cpp	2013-10-15 11:02:55.629263422 +0200
@@ -200,7 +200,9 @@
 
 	/* Read configuration and theme */
 	cfg = new Cfg;
-	cfg->readConf(CFGFILE);
+	char *cfgfile = getenv("SLIM_CFGFILE");
+	if (!cfgfile) cfgfile = CFGFILE;
+	cfg->readConf(cfgfile);
 	string themebase = "";
 	string themefile = "";
 	string themedir = "";
@@ -208,7 +210,9 @@
 	if (testing) {
 		themeName = testtheme;
 	} else {
-		themebase = string(THEMESDIR) + "/";
+		char *themesdir = getenv("SLIM_THEMESDIR");
+		if (!themesdir) themesdir = THEMESDIR;
+		themebase = string(themesdir) + "/";
 		themeName = cfg->getOption("current_theme");
 		string::size_type pos;
 		if ((pos = themeName.find(",")) != string::npos) {
szko-scripts'>koszko-scripts</option>
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<tr class='logheader'><td><span title='2021-01-27 16:43:51 +0100'>2021-01-27</span></td><td class='logsubject'><a href='/guix/commit/gnu/packages/search.scm?id=d8aa4444688ce244d2556630c3f7cfe739e01310'>gnu: Add ugrep.</a></td><td>Hartmut Goebel</td></tr>
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* gnu/packages/search.scm (ugrep): New Variable.


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<tr class='logheader'><td><span title='2021-01-18 01:34:53 +0100'>2021-01-18</span></td><td class='logsubject'><a href='/guix/commit/gnu/packages/search.scm?id=cbc2c28ad4337781c679b7588a74740b2ba7d189'>gnu: xapian, python-xapian-bindings: Update to 1.4.18.</a></td><td>Tobias Geerinckx-Rice</td></tr>
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* gnu/packages/search.scm (xapian, python-xapian-bindings): Update to 1.4.18.


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<tr class='logheader'><td><span title='2021-01-03 06:55:40 +0100'>2021-01-03</span></td><td class='logsubject'><a href='/guix/commit/gnu/packages/search.scm?id=78a9cfa33e66c5647cea66980d83f49a43e27f60'>gnu: perl-search-xapian: Update to 1.2.25.4.</a></td><td>Tobias Geerinckx-Rice</td></tr>
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* gnu/packages/search.scm (perl-search-xapian): Update to 1.2.25.4.


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