socket_get_option

参数

socket

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

level

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.

optname

Available Socket Options

Option	Description	Type
SO_DEBUG	Reports whether debugging information is being recorded.	int
SO_BROADCAST	Reports whether transmission of broadcast messages is supported.	int
SO_REUSEADDR	Reports whether local addresses can be reused.	int
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.	int
SO_LINGER	Reports whether the socket lingers on socket_close() if data is present. By default, when the socket is closed, it attempts to send all unsent data. In the case of a connection-oriented socket, socket_close() will wait for its peer to acknowledge the data. If l_onoff is non-zero and l_linger is zero, all the unsent data will be discarded and RST (reset) is sent to the peer in the case of a connection-oriented socket. On the other hand, if l_onoff is non-zero and l_linger is non-zero, socket_close() will block until all the data is sent or the time specified in l_linger elapses. If the socket is non-blocking, socket_close() will fail and return an error.	array. The array will contain two keys: l_onoff and l_linger.
SO_OOBINLINE	Reports whether the socket leaves out-of-band data inline.	int
SO_SNDBUF	Reports the size of the send buffer.	int
SO_RCVBUF	Reports the size of the receive buffer.	int
SO_ERROR	Reports information about error status and clears it.	int (cannot be set by socket_set_option())
SO_TYPE	Reports the socket type (e.g. SOCK_STREAM).	int (cannot be set by socket_set_option())
SO_DONTROUTE	Reports whether outgoing messages bypass the standard routing facilities.	int
SO_RCVLOWAT	Reports the minimum number of bytes to process for socket input operations.	int
SO_RCVTIMEO	Reports the timeout value for input operations.	array. The array will contain two keys: sec which is the seconds part on the timeout value and usec which is the microsecond part of the timeout value.
SO_SNDTIMEO	Reports the timeout value specifying the amount of time that an output function blocks because flow control prevents data from being sent.	array. The array will contain two keys: sec which is the seconds part on the timeout value and usec which is the microsecond part of the timeout value.
SO_SNDLOWAT	Reports the minimum number of bytes to process for socket output operations.	int