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(PHP 4 >= 4.1.0, PHP 5)
socket_set_nonblock — Sets nonblocking mode for file descriptor fd
$socket
)
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.
socket
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
<?php
$socket = socket_create_listen ( 1223 );
socket_set_nonblock ( $socket );
socket_accept ( $socket );
?>
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.
[#1] kpobococ at gmail dot com [2009-09-11 07:46:02]
Beware, when using this function within a loop (i.e. a demon with a socket). The socket_accept(), for example, emits a warning each time there is no incoming connection available to be read. My php error log file got huge in a matter of seconds, eventually crashing the server.
Of course, i used the @ before the function to take care of that problem.
[EDITOR: One can (and should) use socket_select to detect a new connection on a socket (it's a "readable" event)]