(PHP 4 >= 4.1.0, PHP 5)
socket_set_nonblock — Sets nonblocking mode for file descriptor fd
The socket_set_nonblock() function sets the O_NONBLOCK flag on the socket specified by the socket parameter.
When an operation (e.g. receive, send, connect, accept, ...) is performed on a non-blocking socket, the script will not pause its execution until it receives a signal or it can perform the operation. Rather, if the operation would result in a block, the called function will fail.
A valid socket resource created with socket_create() or socket_accept().
成功时返回 TRUE， 或者在失败时返回 FALSE.
Example #1 socket_set_nonblock() example
This example creates a listening socket on all interfaces on port 1223 and
sets the socket to O_NONBLOCK mode.
socket_accept() will immediately fail unless there is a
pending connection exactly at this moment.
<?php
$socket = socket_create_listen(1223);
socket_set_nonblock($socket);
socket_accept($socket);
?>