REXX Tips & Tricks:Miscellaneous

This section contains some further useful information.

Using PMREXX

The syntax for PMREXX is:

 >>──PMREXX───┬────┬──┬─────────────┬─┬───────────┬─><
              ├─/Q─┤  └─rexxprogram─┘ └─parameter─┘
              └─/T─┘

Where:

/Q

Close PMREXX after the REXX program ends (no "The program has ended" message box)

/T

Start PMREXX in trace mode

rexxprogram

Name of the rexx program

parameter

Parameter for the REXX program

All parameters, except rexxprogram, are optional.

Using PMREXX with the parameter /Q is useful for simple programs which only need to show a PM messagebox (using RxMessageBox). For an example see Saving the Desktop (3.0)

(see Run a REXX program under a specific environment on how to force a program to run under PMREXX)

Please note that you cannot use OS/2 commands that change the environment in a REXX program running under PMREXX. You have to use a similar REXX function for that purpose (e.g. directory() instead of CD, VALUE() instead of SET, etc.).

Warning: The default address environment for a REXX program started via PMREXX in WARP 3 is PMREXX; the default environment in WARP 4 is CMD. Therefore, you cannot distinguish between the environments using ADDRESS() in WARP 4!

Note

see also PMPopup/2 if you only want to use simple dialog boxes in REXX programs.

Prevent REXX from creating a token image

Set the read-only attribute of REXX cmds for which the REXX interpreter should not create a token image (or copy them to a read-only disk or to a filesystem not supporting Extended Attributes).

"Undocumented" REXX functions

The following REXX functions to work with DBCS mixed Strings are only documented in the IBM: OS/2 2.0 Procedures Language/2 Reference Manual and in the Object-Oriented REXX online documentation:

• DBADJUST
• DBBRACKET
• DBCENTER
• DBLEFT
• DBRIGHT
• DBRLEFT
• DBRRIGHT
• DBTODBCS
• DBTOSBCS
• DBUNBRACKET
• DBVALIDATE
• DBWIDTH

Well, for the "normal" REXX programmer only two of these functions are interesting (The functions also work with SBCS strings):

Name       DBRLEFT( string, n {,option} ) 
Function   Delete n chars beginning with the first char 
Example    DBRLEFT( "ABCDEFG", 2 ) gives "CDEFG"
Note       The parameter option is only needed for DBCS strings)
           For SBCS strings you should not use this parameter.

Name       DBRRIGHT( string, n {,option} ) 
Function   Delete n chars beginning with the last char 
Example    DBRRIGHT( "ABCDEFG", 3 ) gives "ABCD"
Note       The parameter option is only needed for DBCS strings)
           For SBCS strings you should not use this parameter.