merge-base: teach "--fork-point" mode

diff --git a/run-command.c b/run-command.c
index aece872e331caa28bf515c98f5cceb27d8414dff..1b7f88eeb1f1971f1568d5991978192c2d00645e 100644 (file)
--- a/run-command.c
+++ b/run-command.c
@@ -76,7 +76,10 @@ static inline void close_pair(int fd[2])
 static inline void dup_devnull(int to)
 {
        int fd = open("/dev/null", O_RDWR);
-       dup2(fd, to);
+       if (fd < 0)
+               die_errno(_("open /dev/null failed"));
+       if (dup2(fd, to) < 0)
+               die_errno(_("dup2(%d,%d) failed"), fd, to);
        close(fd);
 }
 #endif