API Receiver Variable Size Optimization

["David Keck" <dkeck@xxxxxxx>]

The System API Programming manual for V4R1 suggests a technique for optimizing storage allocation when establishing receiver variable sizes as shown at the following address ... http://publib.boulder.ibm.com/cgi-bin/bookmgr/BOOKS/QB3AVC00/2.7.1

The following is an extract from that page of the manual ...

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Depending on the capabilities of your high-level language, some API users take advantage of the following technique to avoid guessing the appropriate size for the receiver variable:

1. Call the API with a receiver variable length of 8 bytes (that is, just enough for the bytes available and the bytes returned fields).
2. Dynamically allocate an amount of storage equivalent to the bytes available.
3. Set the length of receiver variable parameter to the amount of storage allocated.
4. Pass the address of the storage allocated in step 2 by using pass by value (directly).

This technique provides for highly flexible use of APIs that can return variable amounts of data.

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Step one is clear enough, however, steps 2,3,4 are not.  Is this technique applicable to RPG/IV ?  If not then what ?