HP MPE/iX 6.x Operating System NOBREAK , which disables the BREAK k ey for UDC execution, A parameter without a default v alue is required to execute the UDC

A User-De￿ned Command (UDC) ￿le is a text ￿le that con tains one or more command

de￿nitions and with a name for eac h de￿nition. Eac h de￿nition is a UDC. You can use a UDC to perform sev eral MPE/iX commands in succession b y issuing only the name of the UDC. You can also use a UDC to disable an MPE/iX command. Y ou can create the UDC ￿le b y using Editor or TDP .

Each UDC ￿le command de￿nition in a UDC has the following componen ts: Head: name of the UDC (required) and parameters and defaults (optional). Options (this portion is optional):

LIST , which lists all commands executable when the UDC is in voked. LOGON, which immediately executes the UDC at log on.

NOBREAK , which disables the BREAK k ey for UDC execution.

NOHELP , which disables :HELP for UDC execution (normally :HELP lists the entire UDC ￿le). Body: one or more MPE/iX commands con tained in this UDC.

Separator: one or more asterisks ( *) alone on a line, separating command de￿nitions. Figure 1-5 sho ws an example of a UDC ￿le con taining two UDCs.

Figure 1-5. UDC File Example

This UDC ￿le de￿nes t wo UDCs that accept parameters when executed. The ￿rst UDC purges one or more ￿les. The second one runs a program. The follo wing rules apply to parameter speci￿cations:

Parameters can ha ve any name that starts with an alphabetic c haracter and has no special characters, suc h as $ or %.

A parameter without a default v alue is required to execute the UDC.

An exclamation poin t (!) indicates that the follo wing string is a parameter. If no exclamation poin t appears, MPE/iX processes the string as part of the command.

If the default value speci￿ed for a parameter con tains a special c haracter other than $ or #, the default must be delimited b y double quotation marks ( ").

1-20 OVERVIEW