socket_get_option

(PHP 4 >= 4.3.0)

socket_get_option -- Gets socket options for the socket

Description

mixed socket_get_option ( resource socket, int level, int optname)

警告

本扩展模块是实验性的。该模块的行为,包括其函数的名称以及其它任何关于此模块的文档可能会在没有通知的情况下随 PHP 以后的发布而改变。我们提醒您在使用本扩展模块的同时自担风险。

The socket_get_option() function retrieves the value for the option specified by the optname parameter for the socket specified by the socket parameter. socket_get_option() will return FALSE on failure.

The level parameter specifies the protocol level at which the option resides. For example, to retrieve options at the socket level, a level parameter of SOL_SOCKET would be used. Other levels, such as TCP, can be used by specifying the protocol number of that level. Protocol numbers can be found by using the getprotobyname() function.

表格 1. Available Socket Options

OptionDescription
SO_DEBUG Reports whether debugging information is being recorded.
SO_ACCEPTCONN Reports whether socket listening is enabled.
SO_BROADCAST Reports whether transmission of broadcast messages is supported.
SO_REUSEADDR Reports whether local addresses can be reused.
SO_KEEPALIVE Reports whether connections are kept active with periodic transmission of messages. If the connected socket fails to respond to these messages, the connection is broken and processes writing to that socket are notified with a SIGPIPE signal.
SO_LINGER Reports whether the socket lingers on socket_close() if data is present.
SO_OOBINLINE Reports whether the socket leaves out-of-band data inline.
SO_SNDBUF Reports send buffer size information.
SO_RCVBUF Reports recieve buffer size information.
SO_ERROR Reports information about error status and clears it.
SO_TYPE Reports the socket type.
SO_DONTROUTE Reports whether outgoing messages bypass the standard routing facilities.
SO_RCVLOWAT Reports the minimum number of bytes to process for socket input operations. ( Defaults to 1 )
SO_RCVTIMEO Reports the timeout value for input operations.
SO_SNDLOWAT Reports the minimum number of bytes to process for socket output operations.
SO_SNDTIMEO Reports the timeout value specifying the amount of time that an output function blocks because flow control prevents data from being sent.

注: This function used to be called socket_getopt() prior to PHP 4.3.0