Index: utils/lit/lit/util.py
===================================================================
--- utils/lit/lit/util.py
+++ utils/lit/lit/util.py
@@ -48,7 +48,7 @@
     if not path or os.path.exists(path):
         return
 
-    parent = os.path.dirname(path) 
+    parent = os.path.dirname(path)
     if parent != path:
         mkdir_p(parent)
 
@@ -158,13 +158,13 @@
 # Close extra file handles on UNIX (on Windows this cannot be done while
 # also redirecting input).
 kUseCloseFDs = not (platform.system() == 'Windows')
-def executeCommand(command, cwd=None, env=None):
+def executeCommand(command, cwd=None, env=None, input=None):
     p = subprocess.Popen(command, cwd=cwd,
                          stdin=subprocess.PIPE,
                          stdout=subprocess.PIPE,
                          stderr=subprocess.PIPE,
                          env=env, close_fds=kUseCloseFDs)
-    out,err = p.communicate()
+    out,err = p.communicate(input=input)
     exitCode = p.wait()
 
     # Detect Ctrl-C in subprocess.