Commands and command help

Command prompting and online command help are powerful features of CL commands.

If you have developed one or more of your own CL commands, you know that all of the command prompting capabilities used by IBM^® CL commands are available for you to use for your commands. The same is true for command help; the same capabilities for help provided for IBM-provided commands are also available for you to use to create online help.

The first step is to understand how the connections work between commands and command help.

• Command help information is stored in panel group objects. The symbolic object type for a panel group is *PNLGRP. A help panel group consists of help modules. Each help module has a help module name.
• There are two parameters on the Create Command (CRTCMD) command that make the connection between a command (*CMD) object and an online help panel group: HLPID (Help identifier) and HLPPNLGRP (Help panel group).
• There are four types of command help modules in an online help panel group:
  1. Command-level help module
  2. Parameter-level help module
  3. Command examples help module
  4. Command error messages help module

When you try to view the help for a CL command (for instance, by pressing the F1 (Help) key while prompting the command), i5/OS™ determines whether the command has a help panel group associated with the command. If the command was created specifying a panel group name for the HLPPNLGRP parameter, or was changed by the Change Command (CHGCMD) command to have a help panel group associated with the command, the help stored in the panel group is retrieved, formatted, and displayed. i5/OS attempts to retrieve help from the following help modules in the help panel group:

• A command-level help module that has the same name as the value specified for the HLPID parameter when the command was created or changed. For example, if command STRPAY was created specifying HLPID(STRPAY), i5/OS looks for a help module named STRPAY.
• A parameter-level help module for each command parameter, with the exception of constant parameters. The help module name must be the command's HLPID value followed by a forward slash character followed by the parameter keyword name. For example, if command STRPAY has a HLPID value of STRPAY and a parameter named TITLE, i5/OS looks for a parameter-level help module named STRPAY/TITLE.
• A help module containing one or more examples of using the command. The help module name must be the command's HLPID value followed by a forward slash character followed by COMMAND/EXAMPLES. For example, if command STRPAY has a HLPID value of STRPAY, i5/OS looks for a command examples help module named STRPAY/COMMAND/EXAMPLES.
• A help module containing the list of monitorable messages that may be signaled from the command. The help module name must be the command's HLPID value followed by a forward slash character followed by ERROR/MESSAGES. For example, if command STRPAY has a HLPID value of STRPAY, i5/OS looks for a command examples help module named STRPAY/ERROR/MESSAGES.

When viewing extended CL command help on a 5250 terminal (or using 5250 emulator software), command-level and parameter-level help sections are required, and the examples and error messages help sections are optional. If the command-level help section or any parameter-level help section is not found in the online help panel group, diagnostic message CPF6E01 (Help information is incomplete) is displayed at the bottom of the help display. If the examples or error messages help modules are not found, no diagnostic message is displayed.