Experimental Physics and
Industrial Control System

Mark Rivers via Tech-talk <tech-talk at aps.anl.gov> · Thu, 19 Mar 2020 12:49:14 +0000

> The call for dbGetLinkValue() in device driver file while building with EPICS base-3.15.6 generates error as
        undefined reference to `dbGetLinkValue'

dbGetLinkValue appears to have been removed in 3.15 without mentioning that in the Developer's Guide or the release notes.

In the 3.15.6 Application Developer's Guide (https://epics.anl.gov/base/R3-15/6-docs/AppDevGuide.pdf) it says this:

* dbGetLink: Get value of field referenced by database link (Macro)

* dbGetLinkValue: Get value of field referenced by database link (Subroutine)

However, dbGetLinkValue does not exist in any .h or .c file.  So the documentation does not match the actual API.

Surprisingly to me this change in the API is also not mentioned in the 3.15.* release notes.

Two of the error messages in dbGetLink in dbLink.c still say the function name is dbGetLinkValue, which is incorrect.
./src/ioc/db/dbLink.c:        printf("dbGetLinkValue: Use of poptions no longer supported\n");
./src/ioc/db/dbLink.c:        cantProceed("dbGetLinkValue: Illegal link type %d\n", plink->type);

However, I think the intent all along was that you should get dbGetLink(), not dbGetLinkValue().  Previous dbGetLink was a macro that called dbGetLinkValue().  Now dbGetLink is no longer a macro, it is the C function that you should call.

Mark

________________________________
From: Tech-talk <tech-talk-bounces at aps.anl.gov> on behalf of Anindya Roy via Tech-talk <tech-talk at aps.anl.gov>
Sent: Thursday, March 19, 2020 6:54 AM
To: tech-talk at aps.anl.gov
Subject: error calling dbGetLinkValue in EPICS base-3.15.6

The call for dbGetLinkValue() in device driver file while building with EPICS base-3.15.6 generates error as
        undefined reference to `dbGetLinkValue'

The command line output of buliding ioc is attached for reference.

The same ioc is built with base-3.14.12.7 without error. Kindly help.

Regards
Anindya
VECC
, Kolkata, India

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Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System