Re: Timer callbacks stall out (stop getting called)

["Eric Livingston" <elivings clark net>]

| On Thu, 1 Jul 1999, Eric Livingston wrote:
| >
| > Can anyone tell me why this might be so? What in the gtk library handles
| > timeout function callbacks, and is there a way to troubleshoot this
area?
| >
|
| Well, it works by calling select() with a timeout, IIRC. Seems like
| someone would have noticed if that was broken. Perhaps the kernel release
| notes say something about select() behavior.
|
| If this was in a freshly-written program, I could guess wildly that the
| timeout incorrectly had a void return value; since a gint is expected, Gtk
| gets garbage. A non-zero return leaves the timeout in place, but sooner or
| later the garbage might happen to be 0. (OK, not likely but possible.)
|
| Havoc

Well, something's definately amiss with gtk, I'm thinking. I rechecked the
callback function, and it's reliably returning a TRUE (it's of type gint as
well). After several iterations of returning TRUE, it simply is no longer
called, while the rest of the program works fine (the non-time related
stuff...)

I took a look at select(), and things seem ok. I also tested a very small
program, below, that works reliably for extended periods of time, so I don't
think select() is itself the problem... something else is up.

------- select test program (from the man page example,
modified) -----------

#include <stdio.h>
#include <sys/time.h>
#include <sys/types.h>
#include <unistd.h>

int
main(void)
{
        fd_set rfds;
        struct timeval tv;
        int retval;

        while (1) {
                tv.tv_sec = 1;
                tv.tv_usec = 0;
                FD_ZERO(&rfds);
                FD_SET(0, &rfds);
                retval = select(1, &rfds, NULL, NULL, &tv);

                if (retval) {
                        printf("Done.\n");
                        break;
                }
                else {
                        printf("Hit any key to exit...\n");
                }
        }
        exit(0);
}