Operational descriptors

Can anyone tell me how to specify operational descriptors for a main procedure. 
 I have 
OPDESC on the prototype and procedure interface but get an error "operational 
descriptors 
not passed" when the program is called.  Is this because you can't pass 
operational 
descriptors to a main procedure?   This procedure is an OPM interface to a 
sub-procedure 
that receives highly variable parms.  I have found that callprc to a 
sub-procedure does 
pass operational descriptors.  I may just have to use %len(%trimr()) to set the 
length and 
require that they be declared at the maximum width in OPM programs.  
%len(%trimr()) for a 
long field takes a hemosecond to execute.

Can anyone tell me the "correct" way to specify a main procedure with a 
prototype?  The 
manual is vague.  I have settled on the name Main for the prototype and 
procedure 
interface.  I also found a that a main procedure will loop if you specify a 
begin and 
end procedure.  Found that through trial and error while trying to get the 
OPDESC to 
work.  This means that a main procedure cannot be used as a sub-procedure.

One more question.  What is the best way to pass omittable parms through a 
program?  
I don't understand why a parameter passed by reference can't just be passed 
through 
to a another procedure with the associated descriptors, etc. intact.  Is there 
a trick?  
All I get is a reference to a parameter not passed.  Depending on the number of 
omittable parameters I have had to code up to 25 different calls in a case 
statement.  In 
another case I had to use subroutines and copy source because there would have 
been hundreds of possible combinations.

Thanks,

David Morris
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
                                                                                
 
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