QUARK_QUEUE_GET_EPOLLFD(3) Library Functions Manual QUARK_QUEUE_GET_EPOLLFD(3)

quark_queue_get_epollfd — fetch a file descriptor suitable for blocking with epoll_wait(2)

#include <quark.h>

int
quark_queue_get_epollfd(struct quark_queue *qq);

quark_queue_get_epollfd retrieves a epoll file descriptor with all the backend related descriptors already registered to it. This is to be used for integrating quark into an existing main-loop, as in, not calling quark_queue_block(3) at all.

It is to establish a reasonable timeout when you call epoll_wait(2) on it. Some backends will only make the file descriptor readable once a certain watermark of bytes have been read, so without the timeout you might get very late events. 100ms is a safe value, the user should then call quark_queue_get_event(3) to fetch the expired event.

Returns the epoll file descriptor or -1 if deemed invalid, as trying to get the descriptor of a closed queue. errno is set.

#include <sys/epoll.h>

#include <quark.h>

static int
my_own_blocking(struct quark_queue *qq)
{
	int epollfd;

	epollfd = quark_queue_get_epollfd(qq);
	if (epollfd == -1)
		return (-1);
	if (epoll_wait(qq->epollfd, &ev, 1, 100) == -1)
		return (-1);

	return (0);
}

quark_event_dump(3), quark_process_lookup(3), quark_queue_block(3), quark_queue_close(3), quark_queue_default_attr(3), quark_queue_get_event(3), quark_queue_get_stats(3), quark_queue_open(3), quark(7), quark-btf(8), quark-mon(8), quark-test(8)

December 1, 2024 Linux