Hi,
Nan Xiao wrote on Fri, Apr 20, 2018 at 05:28:01PM +0800:
> FYI, thanks!
No. Read the manual page and /sys/kern/kern_time.c :
With a valid clock id and a valid address, this function
cannot fail, so you are just adding dead code. Worse,
you are making future auditors wonder what the heck is
going on here.
Yours,
Ingo
> Index: time.c
> ===================================================================
> RCS file: /cvs/src/usr.bin/time/time.c,v
> retrieving revision 1.25
> diff -u -p -r1.25 time.c
> --- time.c 21 Aug 2017 13:38:02 -0000 1.25
> +++ time.c 20 Apr 2018 09:21:59 -0000
> @@ -76,7 +76,8 @@ main(int argc, char *argv[])
> if (argc < 1)
> usage();
>
> - clock_gettime(CLOCK_MONOTONIC, &before);
> + if (clock_gettime(CLOCK_MONOTONIC, &before))
> + err(1, "clock_gettime");
> switch(pid = vfork()) {
> case -1: /* error */
> warn("fork");
> @@ -92,7 +93,8 @@ main(int argc, char *argv[])
> signal(SIGQUIT, SIG_IGN);
> while (wait3(&status, 0, &ru) != pid)
> ;
> - clock_gettime(CLOCK_MONOTONIC, &after);
> + if (clock_gettime(CLOCK_MONOTONIC, &after))
> + err(1, "clock_gettime");
> if (WIFSIGNALED(status))
> exitonsig = WTERMSIG(status);
> if (!WIFEXITED(status))
