touch: prevent file creation race between utimensat() and open() - sbase - suckless unix tools
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       ---
   DIR commit 23160db9e0b545cead16ac48f23dc31eff2f1b1b
   DIR parent 004a51426e42d42150a746dc113ad86fb3fbed3c
  HTML Author: Michael Forney <mforney@mforney.org>
       Date:   Tue, 17 Mar 2026 01:09:29 -0700
       
       touch: prevent file creation race between utimensat() and open()
       
       If another process creates the file after we determined it was
       missing, touch would fail on open() due to O_EXCL. This failure
       doesn't serve any purpose; we want to update the mtime either way.
       
       Diffstat:
         A tests/0052-touch.sh                 |      13 +++++++++++++
         M touch.c                             |       2 +-
       
       2 files changed, 14 insertions(+), 1 deletion(-)
       ---
   DIR diff --git a/tests/0052-touch.sh b/tests/0052-touch.sh
       @@ -0,0 +1,13 @@
       +#!/bin/sh
       +
       +tmp1=tmp1.$$
       +tmp2=tmp2.$$
       +
       +trap 'rm -f $tmp1 $tmp2' EXIT
       +trap 'exit $?' HUP INT TERM
       +
       +../touch -t 200711121015 $tmp1
       +
       +echo 'Modify: 2007-11-12 10:15:00.000000000' > $tmp2
       +
       +stat $tmp1 | awk '/^Modify:/ {$4 = ""; print}' | diff -wu - $tmp2
   DIR diff --git a/touch.c b/touch.c
       @@ -26,7 +26,7 @@ touch(const char *file)
                        eprintf("utimensat %s:", file);
                if (cflag)
                        return;
       -        if ((fd = open(file, O_WRONLY | O_CREAT | O_EXCL, 0666)) < 0)
       +        if ((fd = open(file, O_WRONLY | O_CREAT, 0666)) < 0)
                        eprintf("open %s:", file);
                ret = futimens(fd, times);
                close(fd);