Experimental Physics and
Industrial Control System

Bruce Hill <[email protected]> · Mon, 4 Apr 2016 13:49:49 -0700

Hi Martin,

I think the dbLoad* routines only support simple macro substitution and

not the

full msi feature set, so I think you're best trying to do this at build

time by invoking

msi twice.

The .db and .substitutions suffixes are significant as RULES.Db knows

how to build

%.db from %.substitutions, but I think you can use anything in place of

.template,

including another .db.

I solved this need for multiple substitutions several years ago by

creating a new

%.db: %.sub2 rule in my local Db/Makefile, but I think it's easier to do

this by having

two directories. For example, you could create a module for your

device that builds

mydevice.db, and then your ioc Db directory could have another

substitutions file

that creates a single db file w/ all 60 instances.

You could also create a deviceDb folder in your ioc/*App directory as

long as you

add a dependency so deviceDb gets built before Db.

Cheers,
- Bruce

On 4/4/2016 11:43 AM, Konrad, Martin wrote:

Hi all,
I need to create an EPICS database for a soft IOC with 60 identical
devices. Each of these devices has a set of records that are identical
for multiple inputs. Having the DRY pattern in mind, I was wondering if
I could somehow use two levels of DB templates. Here is what I have in mind:

st.cmd:
dbLoadTemplate("myproject.substitutions")

myproject.substitutions:
global { SYS=...,SUBSYS=... }
file mydevice.db {
    pattern { ... }
    { ... }
    { ... }
}

mydevice.db:
<some records here>
substitute "INPUT=1"
include "myinput.db"
substitute "INPUT=2"
include "myinput.db"

myinput.db:
<a couple of records needed for each input>

A manual run of MSI tool on mydevice.db handles both the "substitute"
and the "include" keyword correctly but by default macro expansion is
done at dbLoadTemplate time. This however results in

Error: syntax error
   at or before "substitute" in file "mydevice.db" line 16

It seems like dbLoadTemplate doesn't support the "substitute" keyword. I
found a BNF definition of the substitution file format in chapter 6.12.1
of the Application Developer's Guide [1]. Unfortunately I did not find a
definition like this for DB files/templates. Can you please help me out
here?

I am aware that I could use 60 dbLoadTemplate lines instead (that would
clutter IOC boot output, though). I could also pull in both mydevice.db
and myinput.db from the substitutions file directly - but for that I
need to add N lines referring to myinput.db in the substitution file for
each line referring to mydevice.db (assuming a device with N inputs). Is
there a nicer way to do this?

Thanks a lot,

Martin

P.S.: BTW: Is there a difference between a DB file and a template? Are
their file names supposed to have different suffix (".template" vs. ".db"?

[1] http://www.aps.anl.gov/epics/base/R3-15/3-docs/AppDevGuide.pdf

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System