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SIM2000 Date & Time Simulator for VSE & zOS

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SIM2000 - Date and Time Simulation Tool for zOS, OS/390, MVS, VSEtime facility

Date and time simulation in mainframe systems is vital for a numbner of reasons. Although the "Y2K Doomsday" has long since passed, there are many occasions when the need to set an artificial date or time or to advance / retard the clock by a certain amount is necessary.

SIM2000 is a complete date & time simulator for users of z/OS and z/VSE, as well as older versions of VSE and MVS. SIM2000 is completely under your control to tell it which parts of your work you want it to present a "fake date" to, whether it is a whole stream of jobs, a single online transaction or anything in between. It can be used securely in development, production and didaster recovery environments.



Why simulate "fake" dates and times on IBM mainframes?

There are many reasons to have date and time simulation software available including:-

  • Provide remote users with their local time and date rather than data center time - increasingly important for outsourced data centers
  • Test for unusual dates - 29th February, month-end falling on a public holiday, year-end, month end and end of accounting cycle testing
  • Test for unusual times - CICS transactions and batch jobs that run over midnight
  • Production re-runs - ensure a job re-run at 7 a.m. gives the same results as if it had run successfully at 9 p.m. the day before
  • Production consistency - ensure overnight production doesn't suddenly change date in mid-stream
  • Disaster recovery - run last week's work at the same time as running this week's work
  • Transaction synchronization for online systems - display the correct local date and time on terminals on the other side of the country or the other side of the world
  • Make sure your "date windowing" code will work - not wishing to get you panicking but the 2010 date a lot of companies chose is here!
  • Thinking ahead, the hardware TOD clock rolls over just before midnight on September 17th, 2042 - SIM2000 will help you handle it.

SIM2000 lets you test batch and CICS applications in your current environment without interrupting vital production and development work. SIM2000 can be started and stopped at any time without an IPL or recycling of CICS. System auditors love it as a way of verifying correct future program operation.

SIM2000 batch work date / time testing

SIM2000 simulation for batch work lets you set a date for a specific partition, job class or region. Every program running in that partition, class or region sees the simulated date. SIM2000 batch allows you to set the date for:

  • The duration of the executing program (EXEC step)
  • The duration of the entire job (JOB)
  • Specific or generic job names, program names, userids
  • All programs executing in a specific VSE dynamic class
  • All programs running in a specific z/OS class
  • A combination of the conditions above

SIM2000 date simulation can be stopped or changed at any time without needing to IPL.

SIM2000 CICS date / time testing

SIM2000 CICS allows date & time simulation at program and transaction level in any active CICS. Its menu driven transaction lets you set up the SIM2000 CICS controls. SIM2000 CICS will allow you to simulate dates and times at the:

  • Program level (CICS PPT,CICS program)
  • Transaction level (CICS PCT, CICS transaction/task)
  • Terminal level (CICS TCT, CICS terminal)
  • Any combination of the above levels including generic names
  • SIM2000 CICS supports both command and macro level programs, and any programming language supported by CICS.

    SIM2000 STCK Instruction Simulation

    Programs that use the STCK instruction to obtain the current date and time can see the "fake" date using the SIM2000 STCK instruction support. It works in a all batch and online environments.


    SIM2000/DB2 lets DB2 users test DB2 application programs with a "fake" date that is used for all DB2 fields that reflect the time and date.

    SIM2000 Program Analyzer

    The SIM2000 Program Analyzer identifies which executable programs contain date handling code. The SIM2000 Program Analyzer is a batch program that analyzes executable programs contained in zOS loadlibs and VSE libraries.

    The SIM2000 Program Analyzer will identify the programs that use any or all of the following date and time facilities:

  • Store Clock instruction - STCK
  • Cobol CURRENT-DATE usage
  • CICS time related functions
  • VSE GETIME services
  • zOS TIME service

    SIM2000 is available worldwide from Cobbs Mill Consulting

    This page and all materials included are copyright ©2000 DPE and Associates and ©2005 Cobbs Mill Consulting. All rights reserved.