Re: Proglem doing CA calls after catching a signal

[Eric Norum <norume@aps.anl.gov>]

Robert Soliday wrote:

> int sigint=0;
.
.
.
> /* wrapper for ca_pend_event that allows breaking out early if the
>    flag is set from a signal handler. Unlike ca_pend_event, a timeout
>    of zero will not be converted to infinity. */
> long oag_ca_pend_event(double timeout, int *flag) {
>   long status=ECA_NORMAL;
>
>   if (timeout <= 0)
>     ca_poll();
>   while (timeout > 0) {
>     if (*flag)
>       return(status);
>     if (timeout > 1) {
>       status = ca_pend_event(1);
>       timeout -= 1;
>     } else {
>       status = ca_pend_event(timeout);
>       timeout = 0;
>     }
>   }
>
>   return(status);
> }

I'm not completely up to speed on the latest 'alias/noalias' state of C 
pointers, but I think that it would be safer to add some 'volatile' keywords 
to protect yourself from overzealous optimizers:

volatile int sigint = 0;
.
.
long oag_ca_pend_event(double timeout, volatile int *flag) {
.
.

--
Eric Norum                                 norume@aps.anl.gov
Advanced Photon Source                     Phone: (630) 252-4793
Argonne National Laboratory