cobol CALL statement SLEEPY TIME
Example
CALL is also a way to extend COBOL functionality, and also to allow the reusability of code. It can also give access to "system" functionality.
This example illustrates ways to provide "sleep" functionality to IBM Mainframe COBOLs. Bear in mind that the requirement to do so is rare to the extent that usually when someone thinks they need to "sleep" for some reason, it is the wrong thing to do.
ILBOWAT0 is from the old COBOL-specific runtime era on Mainframes. BXP1SLP and BXP4SLP are Unix System Services (USS) routines which can be used by any language. Effectively they are Unix "sleep" requests.
The current IBM Mainframe Runtime (Language Environment (LE)) provides for inter-language communication, and the CEE3DLY LE services is shown in another example, Using z/OS Language Environment thread delay service.
ILBOWAT0 has been around for a very long time (perhaps more than 40 years), and you may still come across it. It's use should be replaced by CEE3DLY or BXP1SLP, whichever is the more appropriate for the particular requirement.
Sometimes you need to cause a program to sleep, or cause a Job to sleep for a while (after an FTP or NDM step), which are usually run as separate jobs, and you would need to sleep/loop looking for the resulting datasets.
Here is a cute little COBOL program to do said task, calling the COBOL sleep programs available in OS/VS and perhaps other legacy and current mainframe operating environments.
IDENTIFICATION DIVISION.
PROGRAM-ID. SLEEPYTM.
ENVIRONMENT DIVISION.
DATA DIVISION.
WORKING-STORAGE SECTION.
01 WAIT-PARM.
05 WAIT-TIME PIC S9(8) COMP VALUE 90.
05 WAIT-RESPONSE PIC S9(8) COMP VALUE 0.
05 WAIT-PROGRAM-24BIT PIC X(8) VALUE 'ILBOWAT0'.
05 WAIT-PROGRAM-31BIT PIC X(8) VALUE 'BPX1SLP '.
05 WAIT-PROGRAM-64BIT PIC X(8) VALUE 'BPX4SLP '.
PROCEDURE DIVISION.
GENESIS.
DISPLAY 'START CALLING WAIT PROGRAM'
CALL WAIT-PROGRAM-24BIT USING WAIT-TIME WAIT-RESPONSE
DISPLAY 'END CALLING WAIT PROGRAM'
GOBACK
PERIOD .
