>I think that was me! We had a few rather large procedures that we
>wanted to implement as independent XLs for NM programs, with switch
>stubs for CM programs, but since the procedures implemented as
>independent XLs were calling procedures in other XLs, the switch
>stubs wouldn't work.
 
I'm not sure why this wouldn't work.
I've done this to implement XCMD-type (DLL-type, for Denys) extensions
so that a system I wrote for a client can be extended without modifying
the original source code. The user specifies the name of the library
at run time; the main system calls HPGETPROCPLABEL to load the procedure
and get its address.
 
You need to be writing in a language that
permits calls through procedure pointers; if you're working in COBOL
or another language that lacks the facility, you can write small
stubs in Pascal or C that will call a routine from an arbitrary XL
specified at run-time.
 
-- Bruce Toback
OPT, Inc.
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