Re: RT Sigio broken on 2.4.19-pre8

[Dan Kegel <dank@kegel.com>]

Aaron Sethman wrote:
> > > Using the Dan Kegel's Poller_bench utility I noticed that RT SIGIO is not
> > > working on 2.4.19-pre8.  Basically sigtimedwait() is always returning
> > > SIGIO.  Note that 2.4.18 works fine.
> > > ... It seems rtsig-nr keeping rising slowly as the system runs.

That sounds like the way I'm clearing the signal queue is not working.
Here's a minimal test case for clearing the signal queue.  Could
you try it and tell me what it says?
- Dan

#include <stdio.h>
#include <signal.h>
#include <assert.h>

int main(int argc, char **argv)
{
        sigset_t sigset;
        siginfo_t info;
        static struct timespec timeout = {0,0};

        // block delivery of SIGRTMIN
        sigemptyset(&sigset);
        sigaddset(&sigset, SIGRTMIN);
        assert(0 == sigprocmask(SIG_BLOCK, &sigset, NULL));

        // clear signal queue
        assert(0 == signal(SIGRTMIN, SIG_IGN)); // POSIX says this clears the queue

        // Make sure that cleared the queue.  (Note that timeout is zero here.)
        assert(sigtimedwait(&sigset, &info, &timeout) != SIGRTMIN);

        printf("test passed\n");
        exit(0);
}