diff -r 1527f40de3b3 -r 5bc7ff103081 hgext/gpg.py
--- a/hgext/gpg.py	Sat Mar 10 15:50:09 2018 +0900
+++ b/hgext/gpg.py	Sat Mar 10 15:57:16 2018 +0900
@@ -60,11 +60,11 @@
         try:
             # create temporary files
             fd, sigfile = tempfile.mkstemp(prefix="hg-gpg-", suffix=".sig")
-            fp = os.fdopen(fd, pycompat.sysstr('wb'))
+            fp = os.fdopen(fd, r'wb')
             fp.write(sig)
             fp.close()
             fd, datafile = tempfile.mkstemp(prefix="hg-gpg-", suffix=".txt")
-            fp = os.fdopen(fd, pycompat.sysstr('wb'))
+            fp = os.fdopen(fd, r'wb')
             fp.write(data)
             fp.close()
             gpgcmd = ("%s --logger-fd 1 --status-fd 1 --verify "