better pid behaviour. we now in process list if pid contained in gajim.pid is...

better pid behaviour. we now in process list if pid contained in gajim.pid is still gajim. fixes #2165. (Linux only)

src/gajim.py

@@ -145,7 +145,26 @@
 config_filename = gajimpaths['CONFIG_FILE']
 
 import dialogs
-if os.path.exists(pid_filename):
+def pid_alive():
+	if os.name == 'nt':
+		if os.path.exists(pid_filename):
+			return True
+		return False
+	try: 
+		pf = open(pid_filename)
+		pid = int(pf.read().strip())
+		pf.close()
+		f = open('/proc/%d/status'% pid) 
+		n = f.readline()
+		f.close()
+		n = n.split()[1].strip()
+		if n == 'gajim':
+			return True 
+	except:
+		pass
+	return False
+
+if pid_alive():
 	path_to_file = os.path.join(gajim.DATA_DIR, 'pixmaps/gajim.png')
 	pix = gtk.gdk.pixbuf_new_from_file(path_to_file)
 	gtk.window_set_default_icon(pix) # set the icon to all newly opened wind
@@ -168,7 +187,8 @@
 if not os.path.exists(pid_dir):
 	check_paths.create_path(pid_dir)
 # Create pid file
-f = open(pid_filename, 'a')
+f = open(pid_filename, 'w')
+f.write(str(os.getpid()))
 f.close()
 del pid_dir