Using commands, function keys, and light pen or cursor selection

This topic explains how to use the ISPF system commands, the function keys and their default assignments, and the light pen and cursor-select facilities.

You can use commands to request processing functions. These are the levels of commands:
System commands
Provided by the DM component and always available to a user, unless explicitly overridden by an application, a user, or a site.
User or Site commands
Defined by the site administrator (in the ISPF Configuration table) and available to a user, in addition to the system commands.
Application commands
Available to a user throughout the processing of an application.
Function commands
Meaningful only while using a particular function within an application.

System, user, site, and application commands are defined by using command tables. The DM component processes these commands. System, user, site, and application command processing is generally transparent to the dialog functions. For example, HELP is a system command.

Function commands include all commands that are processed by a dialog function. For example, the NUMBER command within the ISPF Editor (option 2) is a function command.

You can enter a command by:

ISPF intercepts all commands, regardless of whether the command is typed in the command field or entered with a function key, light pen, or cursor-select key. The DM component performs the command if it matches an entry in the application, user, or system command table. Otherwise, it is assumed to be a function command and is passed to the dialog function.

You can pass commands to the operating system by entering the appropriate ISPF-provided command (TSO) followed by the actual TSO command. For example:
    ===> TSO LISTC LEVEL(Z77PHJ)
You can stack commands to be run by entering a special delimiter between the commands. For example, entering:
    ===> UPDATE BLDG DEPT NAME; MENU ABC
causes the UPDATE command to run first. When it completes, the MENU command starts. The default delimiter is a semicolon (;), which you can change with the ISPF SETTINGS option (see the Settings (Option 0) topic of the z/OS V2R2 ISPF User's Guide Vol II.
Commands cannot be stacked following the: