Experimental Physics and
Industrial Control System

Hi,
I'm wondering how to handle dependencies between support modules the
right way (TM). Let's say I have the following chain of dependencies:

myIOC -> stream -> calc

Background: StreamDevice includes support for the sCalcRecord. Since I'm
building stream and calc as shared libraries that are shipped as
pre-canned Debian packages I want to build them with all their features
enabled.

The problem: myIOC does not make use of sCalcRecords so I only add the
following lines to its Makefile:

myioc_DBD += stream.dbd
myioc_LIBS += stream

The IOC builds fine but a careful look reveals that dbdExpand.pl prints
the following message:

"Device using undefined record type 'scalcout', place-holder created"

When I try to run the IOC it fails to load the DBD file:

dbLoadDatabase("../../dbd/myioc.dbd",0,0)
Declaration of recordtype(scalcout) preceeded full definition.
Error at or before "}" in file "../../dbd/myioc.dbd" line 5335

The relevant lines are:

5334 recordtype(scalcout) {
5335 }
5336 device(scalcout, INST_IO, devscalcoutStream, "stream")

I understand that the scalcout record not being defined anywhere is a
problem. So I use the following lines in the IOC's Makefile and
everything works as intended:

myioc_DBD += calc.dbd
myioc_DBD += stream.dbd
myioc_LIBS += calc
myioc_LIBS += stream

However, I'm wondering if there is a way I can build stream without
forcing IOC engineers to include a DBD file they aren't using. In other
words: Is there a way to include the relevant calc stuff into stream.dbd
without causing problems on IOCs that are using calc directly?

Any help is appreciated,

Martin

P.S.: I'm using StreamDevice 2.8.8, calc 3.7.1 and Base 3.15.6.

--
Martin Konrad
High Performance Controls Team Leader
Facility for Rare Isotope Beams
Michigan State University
640 South Shaw Lane
East Lansing, MI 48824-1321, USA
Tel. 517-908-7253
Email: [email protected]