Re: [PATCH 2/2] cyclictest: simplify rstat_setup

[Crystal Wood <crwood@redhat.com>]

On Mon, 2026-03-09 at 18:55 -0400, John Kacur wrote:
> 
> On Sun, 1 Mar 2026, Lukas Beckmann wrote:
> > +static void rstat_setup(void)
> > +{
> > +	int fd;
> > +	pid_t pid;
> >  
> > -	if (mptr == (void*)-1)
> > -		fprintf(stderr, "ERROR: mmap, %s\n", strerror(errno));
> > +	pid = getpid();
> >  
> > -	return mptr;
> > -}
> > +	snprintf(shm_name, SHM_BUF_SIZE, "%s%d", "/cyclictest", pid);
> >  
> > -static int rstat_mlock(void *mptr)
> > -{
> > -	int err;
> 
> errno = 0 before the call to shm_unlink for good defensive programming
> other than that the patch looks good, I will do a little more testing

Defensive against the library returning -1 without setting errno?  Seems
a bit paranoid and cluttery... all for the payoff of an "ERROR:
shm_unlink Success" message if it ever does happen *and* the old errno
happened to be ENOENT.

And the current code uses it even in places that print the message
regardless.

-Crystal