CLIST
The older scripting language of TSO, used before REXX to run a list of commands with simple logic.
Also written command list, CLIST language, SYSPROC
A CLIST, short for command list, is a script of TSO commands. It was the main way to automate TSO work before REXX arrived, and many sites still have CLISTs in their logon procedures, ISPF menus and older tools.
CLIST is a simple language. Variables start with an ampersand, as in &DSNAME. It has statements for setting variables, testing conditions, looping, writing messages and reading input. Any line that is not a CLIST statement is treated as a TSO command and run.
CLISTs are stored as members of libraries allocated to the SYSPROC DD name, and you run one by typing its name, or with the EXEC command. REXX execs can be kept in the same libraries, which is why the first line of a REXX exec contains the word REXX in a comment: it tells TSO which language the member is written in.
New scripts are normally written in REXX, which is more powerful and easier to read. You will still need to read CLISTs, though, because the old ones often keep working for decades.
Where can I learn this hands-on?
Right here, at ZedBank. You take a junior job at a simulated bank and learn each part of the work by doing it, with Zed beside you. There's nothing to install.
Start at ZedBankRelated
- REXXA readable scripting language used across the mainframe for automation, tooling and quick one-off tasks.
- REXX execA REXX program, stored as a member in a library and run by name from TSO or ISPF.
- TSO commandA command typed at a TSO prompt or on an ISPF command line to ask the system to do something directly.
- TSOTime Sharing Option: the interactive login environment on z/OS, where you get a command prompt and a session of your own.
- ISPFThe full-screen, menu-driven workbench most people use to do their day-to-day work on z/OS.