Thread: Implementing POSIX Timers on AIX - Holy Moly

Hello,

I have a real simple program that uses the POSIX create_timer() function, which is as follows-this code sample is standard and models other code samples that I've found on POSIX timer implementation:

Code:

void callback(union sigval sigev_value) { printf("In callback()\n"); }

void main()
{
    int rc;
    timer_t *timer_id;
    struct sigevent evp;

    memset((void *)&evp, 0, sizeof(evp));
    timer_id = (timer_id*)malloc(sizeof(timer_id));

    evp.sigev_notify_function = &callback;
    evp.sigev_value.sival_ptr = (void*)timer_id;

    errno = 0;
    if (rc = timer_create(CLOCK_REALTIME, &evp, timer_id)) {

    }

    printf("timer_create() Rtn rc %d error %d\n", rc, errno);
    perror("");
    exit(rc);
}

But when I run it, I get the following output:

% timer
timer_create() Rtn rc -1 Error 0
Invalid Argument

What Invalid Argument? The arguments passed into timer_create are fine. It compiles OK. What could be the problem. Any ideas at all would be helpful.

Thanks,
dedham_ma_man

Try passing in NULL for the evp and see if you still get an error. If you don't, then I'd guess that some additional members of evp need fill'n out.

2.4.2 Realtime Signal Generation and Delivery

I would try setting sigev_notify to SIGEV_THREAD.

gg