diff --git a/ginstall/ginstall.py b/ginstall/ginstall.py
index 5ca5aab..81be82a 100755
--- a/ginstall/ginstall.py
+++ b/ginstall/ginstall.py
@@ -941,7 +941,10 @@
     pass
 
   try:
-    return open(path)
+    if path == '-':
+      return sys.stdin
+    else:
+      return open(path)
   except ValueError:
     pass
 
diff --git a/ginstall/ginstall_test.py b/ginstall/ginstall_test.py
index 8deac64..a4e3c8a 100755
--- a/ginstall/ginstall_test.py
+++ b/ginstall/ginstall_test.py
@@ -21,6 +21,7 @@
 import shutil
 import StringIO
 import struct
+import sys
 import tempfile
 import unittest
 import ginstall
@@ -365,6 +366,21 @@
     total = ginstall.GetMemTotal()
     self.assertTrue(total < 4*1e9)
 
+  def testOpenPathOrUrl(self):
+    # URL
+    two_oh_four = ginstall.OpenPathOrUrl('http://www.gstatic.com/generate_204')
+    self.assertEqual(204, two_oh_four.getcode())
+
+    # on-disk file
+    on_disk_file = tempfile.NamedTemporaryFile()
+    testdata = os.urandom(16)
+    on_disk_file.write(testdata)
+    on_disk_file.flush()
+    self.assertEqual(ginstall.OpenPathOrUrl(on_disk_file.name).read(), testdata)
+
+    # stdin (-)
+    self.assertEqual(ginstall.OpenPathOrUrl('-'), sys.stdin)
+
 
 if __name__ == '__main__':
   unittest.main()