I wrote:
> ssize_t overwrite(int fd,
> const void *data_if_empty,size_t size_if_empty,
> const void *data_if_full,size_t size_if_full,
> int *was_empty);
Bah, rubbish. Make this
ssize_t overwrite(int fd,const void *data,size_t size);
If the pipe/queue is empty, don't write, and return 0. Now, this
could probably be implemented with a flag to send(2) (then this
wouldn't work for pipes, but you could use socketpair(2) for a
similar effect). Example:
void add_signal(int signum)
{
static int signal_set = 0;
int new_signal = 1 << signum;
int sent;
signal_set |= new_signal;
sent = send(fd,&signal_set,sizeof(int),MSG_OVERWRITE);
if (!sent) {
send(fd,&new_signal,sizeof(int),0);
signal_set = new_signal;
}
}
- Werner
-- _________________________________________________________________________ / Werner Almesberger, Buenos Aires, Argentina wa@almesberger.net / /_http://www.almesberger.net/____________________________________________/ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Sat Feb 15 2003 - 22:01:00 EST