From e68e38ad95f6cfae2d619dda179548f2ccc146c2 Mon Sep 17 00:00:00 2001 From: Dirk Zimoch Date: Wed, 10 Jun 2020 17:48:09 +0200 Subject: [PATCH] update RELEASE_NOTES.md about empty arrays --- documentation/RELEASE_NOTES.md | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/documentation/RELEASE_NOTES.md b/documentation/RELEASE_NOTES.md index 6fd80615a..274d65f4e 100644 --- a/documentation/RELEASE_NOTES.md +++ b/documentation/RELEASE_NOTES.md @@ -17,6 +17,36 @@ should also be read to understand what has changed since earlier releases. +### Support for empty arrays + +Several problems with empty arrays have been fixed. + +#### Changed dbr_size_n(TYPE,COUNT) macro + +When called with COUNT=0 the macro no longer returns the number of bytes +required for a scalar (1 element) but for an empty array (0 elements). +Make sure you don't call it with COUNT=0 when you really mean COUNT=1. + +#### Array records + +The soft supports of array records aai, waveform, and subArray as well as +the aSub record type have been fixed to correctly report 0 elements read +when reading empty arrays from an input link. + +#### Array support for dbpf + +The dbpf function now accepts arrays, including empty arrays, as a quoted +whitespace separated list of values. + +#### Scalar records reading from empty arrays + +Scalar records reading from empty arrays via database links are now set to +INVALID/LINK alarm status. +Links have to call dbGet with pnRequest=NULL to be recognised as requests +for scalars. +This changes the semantics of pnRequest=NULL. It is now different from +requesting 1 element, which is counted as an array request and may return +a valid empty array. ## EPICS Release 7.0.4