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CICS Multi Sockets Server

TISRVMSL is the listener included for the CICS Multi Sockets Server implementation.

You must define this listener as a Standard Listener.

Using Server Listener of CA Gen requires the following record in the EZACONFG file:

TYPE=LISTENER, 
TRANID=TIML*, 
TRANTRN=NO, 
TRANUSR=NO, 

Leave the SECEXIT and WLM groups parameters blank.

Set the ACCTIME, GIVTIME and REATIME parameters to a value greater than zero.

CICS definitions are required for:

• The Listener transaction TIML*
• The programs TISRVMSL, TIRSLEXT and TIRSLTMX

Use the following example to run DFHCSDUP:

DEFINE TRANSACTION(TIML*) 
DESCRIPTION(Gen CICS Multi Sockets Server Listener Transaction) 
PROGRAM(TISRVMSL) 
TASKDATALOC(ANY) 
TASKDATAKEY(CICS)

DEFINE PROGRAM(TISRVMSL) 
DESCRIPTION(Gen CICS Multi Sockets Server Listener Program) 
LANGUAGE(ASSEMBLER) 
DATALOCATION(ANY) 
EXECKEY(CICS) 

DEFINE PROGRAM(TIRSLEXT) 
DESCRIPTION(Gen CICS Sockets Server Exit Program) 
LANGUAGE(ASSEMBLER) 
DATALOCATION(ANY) 
EXECKEY(CICS) 

DEFINE PROGRAM(TIRSLTMX) 
DESCRIPTION(Gen CICS Sockets Server Timeout Exit Program) 
LANGUAGE(ASSEMBLER) 
DATALOCATION(ANY) 
EXECKEY(CICS) 

* This transaction identifier can be something other than TIML. The EZACONFG file and the CICS definition must use the same name. Add a GROUP of your choice.

Customizable Multi Sockets Server Listener TIMEOUT values are used in the process of accepting new connections, reading data from the socket, and waiting for a socket to be taken by a server. The server application uses customizable TIMEOUT values to read data from the socket. Each TIMEOUT value includes two timeout fields, to set seconds and microseconds that the SELECT/SELECTEX CICS Socket API calls use. In the TIRSLTMX exit, you can modify the TIMEOUT values that TISRVMSL listener ACCEPT, READ and ERROR processes use. The TIMEOUT values that the TISRVMSL listener TAKESOCKET processes use are in the TIRSLEXT exit.

Note: For more information about each exit, see the User Exit Reference Guide.

The Multi Sockets Server listener program, TISRVMSL, produces error and informational messages. Error messages are always written to the CICS Joblog, using the CSSL TDQ and the information messages are written to a CICS TDQ with the same name as the TISRVMSL' transaction identifier. Informational messages are suppressed when the user defined TDQ does not exist.

When using Multi Sockets Server implementation, the client generates TIRM615E and TIRM709E messages for the following conditions:

• TIRM615E when TISRVMSL cannot receive data from sockets after multiple retries. The CICS Joblog includes a message indicating the problem.
• TIRM709E when TIRSLEXT exit is customized to verify encryption use, but the client request fails to set the encryption flag.

The Multi Sockets Server implementation allows the server to be routed to a CICS region different from the region where the TISRVMSL listener executes. To invoke routing, use the SYSID where the server is to execute or use distributed routing. Use the CICS variable in the TIRSLEXT user exit to set the SYSID. Use the DSRTPGM program or the CICS transaction definition to implement distributed routing.

Note: For more information about the TIRSLEXT user exit, see User Exit Reference Guide.