Checking for NULL field in C when using Record I/O -- C400-L

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Subject: Checking for NULL field in C when using Record I/O
From: Patrik Schindler <poc@xxxxxxxxxx>
Date: Sun, 20 Oct 2024 15:41:38 +0200
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Hello,

either I'm too blind or searching the wrong way.

What is the correct way to know a field being read with e. g. _Readn() is actually NULL, so I can subsequently ignore anything being in the respective field's read buffer?

Actual code can be seen here: https://github.com/PoC-dev/ibmdocs-tools/blob/main/as400/listdocs.c (lines 177 ff, and 188 ff).

Table definition: https://github.com/PoC-dev/ibmdocs-tools/blob/main/as400/ibmdoctypf.dds

Thank you!

:wq! PoC

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Follow-Ups:

Re: Checking for NULL field in C when using Record I/O , Mark Waterbury

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