Sockets

9.2.13t_shutdown()

This function causes all or part of a full duplex connection on the socket associated with socket to be shut down.

Syntax

int t_shutdown(long socket, int how)

Return value

Returns one of the following:

Sockets

9.2.14t_socket()

This function creates an endpoint for communication and returns a descriptor.

Syntax

extern long t_socket (int domain, int type, int protocol)

Return value

Returns one of the following:

socket descriptor

if successful.

Sockets

Usage

SOCK_STREAM sockets are full duplex byte streams, similar to UNIX pipes. A stream socket must be in a connected state before it can send or receive data.

A connection to another socket is created with a t_connect() call. When connected, data can be transferred using t_send() and t_recv(). When a session has been completed, t_socketclose() can be performed. Out-of-band data can also be transmitted and received, as described in the t_send() and t_recv() documentation. See t_send() and t_sendto() on page 9-18 for more details.

The communications protocols used to implement a SOCK_STREAM ensure that data is not lost or duplicated. If a piece of data (for which the peer protocol has buffer space) cannot be transmitted successfully within a reasonable length of time, the connection is considered broken. In this case, calls return with a –1 error and TIMEDOUT is written to the internal variable errno.

The protocols optionally keep sockets warm by forcing transmissions roughly every minute in the absence of other activity. An error is indicated if no response has been received on an otherwise idle connection for an extended period, for example, five minutes.

SOCK_DGRAM sockets allow datagrams to be sent to correspondents named in t_sendto() calls. Datagrams are generally received with t_recvfrom(), which returns the next datagram with its return address.

The operation of sockets is controlled by socket level options. These options are defined in the file socket.h. The t_getsockopt() and t_setsockopt() functions are used to get and set options, respectively (see t_getsockopt() on page 9-10 and t_setsockopt() on page 9-20).

Sockets

9.2.15t_socketclose()

This function deletes a descriptor from the reference table. On the close of a socket, associated naming information and queued data are discarded.

Note

This is just close() on traditional sockets systems.

Syntax

int t_socketclose(long socket)

where:

socket is the identifier of the socket to be closed.

Return value

Returns one of the following:

Sockets