diff --git a/contrib/dumprevlog b/contrib/dumprevlog
--- a/contrib/dumprevlog
+++ b/contrib/dumprevlog
@@ -6,7 +6,7 @@ import sys
 from mercurial import revlog, node, util
 
 for fp in (sys.stdin, sys.stdout, sys.stderr):
-    util.set_binary(fp)
+    util.setbinary(fp)
 
 for f in sys.argv[1:]:
     binopen = lambda fn: open(fn, 'rb')
diff --git a/contrib/simplemerge b/contrib/simplemerge
--- a/contrib/simplemerge
+++ b/contrib/simplemerge
@@ -43,7 +43,7 @@ def showhelp():
 
 try:
     for fp in (sys.stdin, sys.stdout, sys.stderr):
-        util.set_binary(fp)
+        util.setbinary(fp)
     
     opts = {}
     try:
diff --git a/contrib/undumprevlog b/contrib/undumprevlog
--- a/contrib/undumprevlog
+++ b/contrib/undumprevlog
@@ -7,7 +7,7 @@ import sys
 from mercurial import revlog, node, scmutil, util, transaction
 
 for fp in (sys.stdin, sys.stdout, sys.stderr):
-    util.set_binary(fp)
+    util.setbinary(fp)
 
 opener = scmutil.opener('.', False)
 tr = transaction.transaction(sys.stderr.write, opener, "undump.journal")
diff --git a/hg b/hg
--- a/hg
+++ b/hg
@@ -33,6 +33,6 @@ import mercurial.util
 import mercurial.dispatch
 
 for fp in (sys.stdin, sys.stdout, sys.stderr):
-    mercurial.util.set_binary(fp)
+    mercurial.util.setbinary(fp)
 
 mercurial.dispatch.run()
diff --git a/hgext/convert/subversion.py b/hgext/convert/subversion.py
--- a/hgext/convert/subversion.py
+++ b/hgext/convert/subversion.py
@@ -112,8 +112,8 @@ def debugsvnlog(ui, **opts):
     """Fetch SVN log in a subprocess and channel them back to parent to
     avoid memory collection issues.
     """
-    util.set_binary(sys.stdin)
-    util.set_binary(sys.stdout)
+    util.setbinary(sys.stdin)
+    util.setbinary(sys.stdout)
     args = decodeargs(sys.stdin.read())
     get_log_child(sys.stdout, *args)
 
diff --git a/mercurial/hgweb/wsgicgi.py b/mercurial/hgweb/wsgicgi.py
--- a/mercurial/hgweb/wsgicgi.py
+++ b/mercurial/hgweb/wsgicgi.py
@@ -13,8 +13,8 @@ from mercurial import util
 from mercurial.hgweb import common
 
 def launch(application):
-    util.set_binary(sys.stdin)
-    util.set_binary(sys.stdout)
+    util.setbinary(sys.stdin)
+    util.setbinary(sys.stdout)
 
     environ = dict(os.environ.iteritems())
     environ.setdefault('PATH_INFO', '')
diff --git a/mercurial/posix.py b/mercurial/posix.py
--- a/mercurial/posix.py
+++ b/mercurial/posix.py
@@ -128,7 +128,7 @@ def checkosfilename(path):
     Returns None if the path is ok, or a UI string describing the problem.'''
     pass # on posix platforms, every path is ok
 
-def set_binary(fd):
+def setbinary(fd):
     pass
 
 def pconvert(path):
diff --git a/mercurial/sshserver.py b/mercurial/sshserver.py
--- a/mercurial/sshserver.py
+++ b/mercurial/sshserver.py
@@ -21,8 +21,8 @@ class sshserver(object):
         sys.stdout = sys.stderr
 
         # Prevent insertion/deletion of CRs
-        util.set_binary(self.fin)
-        util.set_binary(self.fout)
+        util.setbinary(self.fin)
+        util.setbinary(self.fout)
 
     def getargs(self, args):
         data = {}
diff --git a/mercurial/windows.py b/mercurial/windows.py
--- a/mercurial/windows.py
+++ b/mercurial/windows.py
@@ -96,7 +96,7 @@ def checkexec(path):
 def checklink(path):
     return False
 
-def set_binary(fd):
+def setbinary(fd):
     # When run without console, pipes may expose invalid
     # fileno(), usually set to -1.
     if hasattr(fd, 'fileno') and fd.fileno() >= 0: