1 files changed, 3 insertions, 0 deletions
diff --git a/io.c b/io.c
index 681ba97ec3..debb94a7cd 100644
--- a/io.c
+++ b/io.c
@@ -1859,6 +1859,9 @@ rb_fdopen(fd, mode)
 	    file = fdopen(fd, mode);
 	}
 	if (!file) {
+#ifdef _WIN32
+	    if (errno == 0) errno = EINVAL;
+#endif
 	    rb_sys_fail(0);
 	}
     }