UDCs vs. scripts
option logon
- UDCs only (a script can be executed from an “option logon” UDC)
- logon UDCs executed in this order:
- 1. System level 2. Account level 3. User level (opposite of the non-logon execution order!)
CI command search order:
- A. UDCs ( 1. User level 2. Account level 3. System level)
- thus UDCs can override built-in commands
- B. built-in MPE commands, e.g. LISTFILE
- C. script and program files. HPPATH variable used to qualify unqualified filenames
- :XEQ command allows script to be same name as UDC or built-in command, e.g. :xeq listf.scripts.sys