socket_set_block()

(PHP 4 >= 4.2.0, PHP 5, PHP 7)

Sets blocking mode on a socket resource

说明

socket_set_block(resource $socket): bool

The socket_set_block() function removes the O_NONBLOCK flag on the socket specified by the$socketparameter.

When an operation(e.g. receive, send, connect, accept,...)is performed on a blocking socket, the script will pause its execution until it receives a signal or it can perform the operation.

参数

$socket: A valid socket resource created with socket_create() or socket_accept().

返回值

成功时返回TRUE，或者在失败时返回FALSE。

范例

socket_set_block() example

<?php
$socket = socket_create_listen(1223);
socket_set_block($socket);
socket_accept($socket);
?>

This example creates a listening socket on all interfaces on port 1223 and sets the socket to O_BLOCK mode.socket_accept() will hang until there is a connection to accept.

参见

socket_set_nonblock()Sets nonblocking mode for file descriptor fd
socket_set_option()Sets socket options for the socket

Besides true and false socket_set_block might return NULL if you're not too careful. That would happen when passing non socket resource as first parameter. 
E.g. socket_set_block(false)) would return NULL and emit warning that you're trying to do things with non-socket.