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C and string descriptors?

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The Question is:

 
Wizard-
How do I prototype a function in C which wishes to  take a descriptor as an
argument? i.e., What is the "type" of a descriptor as far as C is concerned.
I'm attempting to build a C interface to a $SMG routine and wish to make the
interface as transparent
 as possible so that I can pass arguments to my C function just like I was
calling the actual FORTRAN routine:
 
C function:
$DESCRIPTOR(descrip1, "Descriptor");
unsigned long keyid;
 
AddKeyDef(&keyid, &descrip1, .....)
 
So, what would the prototype of AddKeyDef look like?
 
Thank you
Patrick Franz

The Answer is :

 
  One potential declaration:
 
    AddKeyDef(unsigned long *, struct dsc$descriptor_s *, ...);
 
  Alternatively (for those disincluded to use the argument verification
  mechanisms), use (void *).
 
  Please look at how the $DESCRIPTOR macro is defined in descrip.h, as
  well as various searches of existing examples in sys$examples: and
  various other related "examples" directories that might be available
  to you.  Also see the discussion of string descriptors in the OpenVMS
  Frequently Asked Questions (FAQ), in "PROG13.  What is a descriptor?".
 
 


  

     
     
answer written or last revised on ( 30-SEP-1999 )

     
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