--- a/mercurial/util.py
+++ b/mercurial/util.py
@@ -161,7 +161,7 @@ def cachefunc(func):
def pipefilter(s, cmd):
'''filter string S through command CMD, returning its output'''
- (pout, pin) = popen2.popen2(cmd, -1, 'b')
+ (pin, pout) = os.popen2(cmd, 'b')
def writer():
try:
pin.write(s)