* io.c (pipe_open): need to set cmd if argc == 0 (win32).

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@7179 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 3 insertions, 0 deletions

diff --git a/io.c b/io.c
index 1b5e7acfa9..0dbb6b741c 100644
--- a/io.c
+++ b/io.c
@@ -2852,6 +2852,9 @@ pipe_open(argc, argv, mode)
 	rb_w32_join_argv(cmd, args);
 	exename = RSTRING(prog)->ptr;
     }
+    else {
+	cmd = StringValueCStr(prog);
+    }
     while ((pid = rb_w32_pipe_exec(cmd, exename, openmode, &fpr, &fpw)) == -1) {
 	/* exec failed */
 	switch (errno) {