Re: [PATCH 1/2] cyclictest: fix growing shm stat file

[John Kacur <jkacur@gmail.com>]

On Sun, 1 Mar 2026, Lukas Beckmann wrote:

> On a received USR2 signal, the current statistics are written to a file
> in shared memory. Before that happens, it is truncated to zero to clear
> it.
> 
> However, currently the shm file keeps growing with each received signal
> because the seek pointer is not updated by ftruncate.
> 
> This is fixed by calling fseek after truncating.
> 
> Signed-off-by: Lukas Beckmann <lbckmnn@mailbox.org>
> ---
>  src/cyclictest/cyclictest.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/src/cyclictest/cyclictest.c b/src/cyclictest/cyclictest.c
> index 191945e..960c905 100644
> --- a/src/cyclictest/cyclictest.c
> +++ b/src/cyclictest/cyclictest.c
> @@ -1472,6 +1472,7 @@ static void sighand(int sig)
>  			return;
>  		}
>  		rstat_ftruncate(rstat_fd, 0);
> +		lseek(rstat_fd, 0, SEEK_SET);
>  		quiet = 0;
>  		dprintf(rstat_fd, "#---------------------------\n");
>  		dprintf(rstat_fd, "# cyclictest current status:\n");
> -- 
> 2.53.0
> 
> 
> 
Signed-off-by: John Kacur <jkacur@redhat.com>