Using immediate commands

Immediate commands are TSO/E REXX commands, provided with the TSO/E implementation of the language. Immediate commands change characteristics that control the execution of an exec or program.

In response to an interrupt signal, usually <Ctrl-C>, the REXX interrupt handler suspends execution of the REXX program and prompts for an immediate command. The command is specified by number. In the z/OS UNIX REXX environment, the following commands are supported:
Command Description
1 Continue execution
2 Issue a Halt Interruption
3 Start trace
4 End trace
5 Halt type
6 Resume type
You can use the rexxopt() function to disable this capability or attach this signal handler to other signals. As with any signal handler, the kernel may defer delivery of the signal depending on what the program is executing at the time.
Note: REXX programs that are run as setuid or setgid programs cannot be interrupted to issue an immediate command.