SHUTDOWN

One way to terminate a network connection is to issue a CLOSE macro that attempts to complete all outstanding data transmission requests prior to breaking the connection. The SHUTDOWN macro can be used to close one-way traffic while completing data transfer in the other direction. The HOW parameter determines the direction of the traffic to shutdown.

A client program can use the SHUTDOWN macro to reuse a given socket with a different connection.

If you issue SHUTDOWN for a socket that currently has outstanding socket calls pending, see Table 1 to determine the effects of this operation on the outstanding socket calls.

The following requirements apply to this call:

Authorization:

Supervisor state or problem state, any PSW key.

Dispatchable unit mode:

Task.

Cross memory mode:

PASN = HASN.

Amode:

31-bit or 24-bit.

Note: See "Addressability mode (Amode) considerations" under CALL instruction API environmental restrictions and programming requirements.

ASC mode:

Primary address space control (ASC) mode.

Interrupt status:

Enabled for interrupts.

Locks:

Unlocked.

Control parameters:

All parameters must be addressable by the caller and in the primary address space.


>>-EZASMI--TYPE=SHUTDOWN--,S--=--+-number---+------------------->
                                 +-address--+   
                                 +-*indaddr-+   
                                 '-(reg)----'   

>--,HOW--=--+-number---+--,ERRNO--=--+-address--+--------------->
            +-address--+             +-*indaddr-+   
            +-*indaddr-+             '-(reg)----'   
            '-(reg)----'                            

>--,RETCODE--=--+-address--+--+---------------------------+----->
                +-*indaddr-+  +-,ECB--=--+-address--+-----+   
                '-(reg)----'  |          +-*indaddr-+     |   
                              |          '-(reg)----'     |   
                              '-,REQAREA--=--+-address--+-'   
                                             +-*indaddr-+     
                                             '-(reg)----'     

>--+-------------------------+--+------------------------+-----><
   '-,ERROR--=--+-address--+-'  '-,TASK--=--+-address--+-'   
                +-*indaddr-+                +-*indaddr-+     
                '-(reg)----'                '-(reg)----'

Keyword

Description

S

Input parameter. A value or the address of a halfword binary number specifying the socket to be shutdown.

HOW

Input parameter. A fullword binary field specifying the shutdown method.

Value: Description
0: Ends further receive operations.
1: Ends further send operations.
2: Ends further send and receive operations.

ERRNO

Output parameter. A fullword binary field. If RETCODE is negative, this field contains an error number. See Socket call error return codes for information about ERRNO return codes.

RETCODE

Output parameter. A fullword binary field that returns the following values:

Value: Description
0: Successful call.
-1: Check ERRNO for an error code.

ECB or REQAREA

Input parameter. This parameter is required if you are using APITYPE=3. It points to a 104-byte field containing:

For ECB: A 4-byte ECB posted by TCP/IP when the macro completes.
For REQAREA: A 4-byte user token (set by you) that is presented to your exit when the response to this function request is complete.
For ECB/REQAREA: The last 100 bytes is a storage field used by the interface to save the state information.

Note: This storage must not be modified until the macro function has completed and the ECB has been posted, or the asynchronous exit has been driven.

ERROR

Input parameter. The location in your program to receive control when the application programming interface (API) processing module cannot be loaded.

TASK

Input parameter. The location of the task storage area in your program.