START

The EXEC CICS START command schedules a new transaction to run now or at a later time.

It is the way one task starts another task, with or without a delay, and passes data to it.

What the START command does

• Starts the transaction named by TRANSID, which creates a brand new task.
• Can start it immediately, or after a delay using the INTERVAL, TIME, AFTER, or AT options.
• The FROM and LENGTH options pass a data area to the new task.
• The new task collects the data with the EXEC CICS RETRIEVE command.

Options of the START command

• TRANSID - the transaction to start. This option is required.
• FROM and LENGTH - the data area passed to the started task.
• INTERVAL(hhmmss) - start after a delay, for example INTERVAL(002000) means 20 minutes from now.
• TIME(hhmmss) - start at a specific time of day.
• REQID - names the request so it can be cancelled later with the CANCEL command.
• TERMID - starts the transaction on a specific terminal instead of in the background.
• PROTECT - makes the request recoverable so it survives a CICS restart.

START and RETRIEVE work together

• START stores the data and schedules the task; the started task issues RETRIEVE to read it.
• If the started program never issues RETRIEVE, the data is simply discarded.
• Typical uses: delayed printing, time-triggered housekeeping, and starting a transaction on another terminal.
• Both commands must agree on the data length and layout, usually through a shared copybook.

Example of starting a delayed transaction

• This starts the print transaction PRNT 20 minutes from now and passes it a 200-byte record.
• *--- start the print transaction 20 minutes from now --- EXEC CICS START TRANSID('PRNT') FROM(PRINT-RECORD) LENGTH(200) INTERVAL(002000) REQID('PRINT01') END-EXEC.
• The REQID lets the program cancel this request later if the user changes their mind.