diff --git a/gitstats b/gitstats
index c71b0e4..b80a9a2 100755
--- a/gitstats
+++ b/gitstats
@@ -57,13 +57,9 @@ def getpipeoutput(cmds, quiet = False):
 		print '>> ' + ' | '.join(cmds),
 		sys.stdout.flush()
 	p = subprocess.Popen(cmds[0], stdout = subprocess.PIPE, shell = True)
-	processes=[p]
 	for x in cmds[1:]:
 		p = subprocess.Popen(x, stdin = p.stdout, stdout = subprocess.PIPE, shell = True)
-		processes.append(p)
 	output = p.communicate()[0]
-	for p in processes:
-		p.wait()
 	end = time.time()
 	if not quiet:
 		if ON_LINUX and os.isatty(1):
@@ -327,7 +323,7 @@ class GitDataCollector(DataCollector):
 
 		# Collect revision statistics
 		# Outputs "<stamp> <date> <time> <timezone> <author> '<' <mail> '>'"
-		lines = getpipeoutput(['git rev-list --pretty=format:"%%at %%ai %%aN <%%aE>" %s' % getlogrange('HEAD'), 'grep -v ^commit']).split('\n')
+		lines = getpipeoutput(['git rev-list --pretty=format:"%%at %%ai %%aN <%%aE>" %s' % getlogrange('HEAD'), 'grep -av ^commit']).split('\n')
 		for line in lines:
 			parts = line.split(' ', 4)
 			author = ''
@@ -434,7 +430,7 @@ class GitDataCollector(DataCollector):
 			self.commits_by_timezone[timezone] = self.commits_by_timezone.get(timezone, 0) + 1
 
 		# outputs "<stamp> <files>" for each revision
-		revlines = getpipeoutput(['git rev-list --pretty=format:"%%at %%T" %s' % getlogrange('HEAD'), 'grep -v ^commit']).strip().split('\n')
+		revlines = getpipeoutput(['git rev-list --pretty=format:"%%at %%T" %s' % getlogrange('HEAD'), 'grep -av ^commit']).strip().split('\n')
 		lines = []
 		revs_to_read = []
 		time_rev_count = []