SYSCMD allows you to run external programs or system
processes from inside the system, thus temporarily
suspending it.

Save and/or restore the screen's graphics image by 
choosing from one of the following options:

NONE - to execute a system command or another program
without exiting the program environment. Regardless of 
your screen setup, the current graphics display is never
changed because the command or program text output is 
suppressed.

TEXT - to execute a system command or another program
without exiting the program environment through the use of
the system's graphics display setup.

GRAPHIC - to execute a system command or another program
without exiting the program environment. This is done
through the use of the system's graphics display, 
regardless of whether or not a two screen configuration
exists. 

SHELL - to enter the operating system environment without
exiting the program environment. The graphics image is
stored and restored after returning to the program,
regardless of whether or not a two screen configuration
exists.
