git-daemon: don't ignore pid-file write failure

Note: since the consequence of failure is to call die,
I don't bother to close "f".

Signed-off-by: Jim Meyering <jim@meyering.net>
Signed-off-by: Junio C Hamano <junkio@cox.net>
diff --git a/daemon.c b/daemon.c
index e74ecac..674e30d 100644
--- a/daemon.c
+++ b/daemon.c
@@ -970,8 +970,8 @@
 	FILE *f = fopen(path, "w");
 	if (!f)
 		die("cannot open pid file %s: %s", path, strerror(errno));
-	fprintf(f, "%d\n", getpid());
-	fclose(f);
+	if (fprintf(f, "%d\n", getpid()) < 0 || fclose(f) != 0)
+		die("failed to write pid file %s: %s", path, strerror(errno));
 }
 
 static int serve(char *listen_addr, int listen_port, struct passwd *pass, gid_t gid)