套接字上下文选项列表

说明

套接字上下文选项可用于所有工作在套接字上的封装协议，像 tcp, http 和 ftp。

可选项

bindto: 用户 PHP 访问网络的指定的 IP 地址（IPv4 或 IPv6 其中的一个）和/或端口号，这个语法是 ip:port. Setting the IP or the port to 0 will let the system choose the IP and/or port.

注意:
As FTP creates two socket connections during normal operation, the port number cannot be specified using this option.
backlog: Used to limit the number of outstanding connections in the socket's listen queue.

注意:
This is only applicable to stream_socket_server().
ipv6_v6only: Overrides the OS default regarding mapping IPv4 into IPv6.

注意:
This is important in particular when trying to listen on IPv4 addresses separately while there exists a binding on [::].

This is only applicable to stream_socket_server().
so_reuseport: Allows multiple bindings to a same ip:port pair, even from separate processes.

注意:
This is only applicable to stream_socket_server().
so_broadcast: Enables sending and receiving data to/from broadcast addresses.

注意:
This is only applicable to stream_socket_server().
tcp_nodelay: Setting this option to true will set SOL_TCP,NO_DELAY=1 appropriately, thus disabling the TCP Nagle algorithm.

更新日志

版本	说明
7.1.0	Added `tcp_nodelay`.
7.0.1	Added `ipv6_v6only`.

范例

示例 #1 Basic bindto usage example


<?php
// connect to the internet using the '192.168.0.100' IP
$opts = array(
    'socket' => array(
        'bindto' => '192.168.0.100:0',
    ),
);


// connect to the internet using the '192.168.0.100' IP and port '7000'
$opts = array(
    'socket' => array(
        'bindto' => '192.168.0.100:7000',
    ),
);


// connect to the internet using the '2001:db8::1' IPv6 address
// and port '7000'
$opts = array(
    'socket' => array(
        'bindto' => '[2001:db8::1]:7000',
    ),
);


// connect to the internet using port '7000'
$opts = array(
    'socket' => array(
        'bindto' => '0:7000',
    ),
);


// create the context...
$context = stream_context_create($opts);

// ...and use it to fetch the data
echo file_get_contents('http://www.example.com', false, $context);

?>