RE: External data structures

I don't code in RPG so even though I've heard of external data structures I
am not sure I know what they mean.
There is of course a structure definition in C and simplest would be:

struct 
{
  char library[10];
  char file[10];
  int  numberOfRecords;
} record;

This defines a record of 24 bytes of length that can be used to use
similarly defined physical file using _Ropen, _Rreadn and like native I/O
functions.

However, one could simply declare:

char record[24];

and use it in the read,update,write functions.  
Hopefully I didn't miss you point.

Elvis


-----Original Message-----
 Subject: [C400-L] External data structures

Folks:

I'm posting this for a co-worker ...

Wondering if anyone would be able give a simple source example of an
external data structure definition in OPM C and ILE C ... if the concept
even exists.

We're looking for examples in a C program that will cause a file or
external data structure to NOT be picked up by a DSPPGMREF.

Thanks!

david