[GRASS-SVN] r58580 - grass/trunk/gui/wxpython/core

[svn_grass at osgeo.org]

Author: huhabla
Date: 2014-01-01 18:56:02 -0800 (Wed, 01 Jan 2014)
New Revision: 58580

Modified:
   grass/trunk/gui/wxpython/core/utils.py
Log:
Fixed wrongly placed os._exit() call, that prevents exit handler from work.
The child should not call os._exit(), otherwise existing subprocesses will not
terminated correctly. os._exit() should be called in the parent.


Modified: grass/trunk/gui/wxpython/core/utils.py
===================================================================
--- grass/trunk/gui/wxpython/core/utils.py	2014-01-02 02:53:00 UTC (rev 58579)
+++ grass/trunk/gui/wxpython/core/utils.py	2014-01-02 02:56:02 UTC (rev 58580)
@@ -1063,12 +1063,23 @@
         # launch GUI in the background
         child_pid = os.fork()
         if child_pid == 0:
+            # To become the session leader of this new session and the process group
+            # leader of the new process group, we call os.setsid().  The process is
+            # also guaranteed not to have a controlling terminal.
+            os.setsid()
             mainfn()
-        os._exit(0)
+        else:      
+            # exit() or _exit()?
+            # _exit is like exit(), but it doesn't call any functions registered
+            # with atexit (and on_exit) or any registered signal handlers.  It also
+            # closes any open file descriptors.  Using exit() may cause all stdio
+            # streams to be flushed twice and any temporary files may be unexpectedly
+            # removed.  It's therefore recommended that child branches of a fork()
+            # and the parent branch(es) of a daemon use _exit().
+            os._exit(0)   # Exit parent of the child.
     else:
         mainfn()
 
-
 def PilImageToWxImage(pilImage, copyAlpha = True):
     """!Convert PIL image to wx.Image