The SH environment

The SH environment is the default host command environment when a REXX program is run from a z/OS shell or from a program using exec(). It is available to a REXX program only in those two situations. In the SH environment, a syscall command runs as a z/OS shell command that has been issued this way:

/bin/sh -c shell_command

All open file descriptors and environment variables are available to the shell command. Note that built-in shell commands run in the shell process, not your REXX process and cannot alter the REXX environment. For example, address sh 'cd /' will not change the current directory of your REXX process.

If you are running the REXX program from a z/OS shell or from a program, the SYSCALL environment is automatically initialized.

See Examples: Using syscall commands for some sample REXX programs that show how REXX and z/OS shell commands can work together—for example, a REXX program that can read output from a z/OS shell command. The mount and unmount sample programs are shipped in the /samples directory as files mountx and unmountx.