use poll() instead of returncode (presumably safer)

gitstatus.py

@@ -9,7 +9,7 @@
 gitsym = Popen(['git', 'symbolic-ref', 'HEAD'], stdout=PIPE, stderr=PIPE)
 branch = gitsym.communicate()[0].strip()
 
-if gitsym.returncode != 0:
+if gitsym.poll():
 	import sys
 	sys.exit(0)
 
@@ -45,7 +45,7 @@
 			remote_ref = 'refs/remotes/%s/%s' % (remote_name, merge_name[11:])
 		revgit = Popen(['git', 'rev-list', '--left-right', '%s...HEAD' % remote_ref],stdout=PIPE, stderr=PIPE)
 		revlist = revgit.communicate()[0]
-		if revgit.returncode != 0: # fallback to local
+		if revgit.poll(): # fallback to local
 			revlist = Popen(['git', 'rev-list', '--left-right', '%s...HEAD' % merge_name],stdout=PIPE, stderr=PIPE).communicate()[0]
 		behead = revlist.splitlines()
 		ahead = len([x for x in behead if x[0]=='>'])