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<== Date ==> <== Thread ==>

Subject: Re: Initializing a record VAL field with a constant
From: Andrew Johnson <[email protected]>
To: [email protected]
Cc: EPICS tech-talk <[email protected]>
Date: Mon, 14 Jun 2004 15:03:58 -0500
J. Frederick Bartlett wrote:

Your suggestion has the expected behavior. Given that setting the VAL and PINI fields correctly initializes the record, why should setting the INP field to a constant value ever be needed? If it is not needed, why does the "Record Reference Manual" discuss the INP method rather than the more intuitive PINI method?

The ability to set the VAL field in a .db file was only added to most record types relatively recently (i.e. since the Record Reference Manual was last updated).


Having an initializable .VAL field is obviously necessary to be able to initialize the two string record types with a constant string - it is impossible for the DOL/INP field processing to distinguish between an initial constant string that just happens to be identical to a CA channel name, and a CA link to a named channel. I'm not sure why this wasn't done originally for all the record types, but it wasn't. We have to maintain the old constant link type behaviour for backwards compatibility reasons, although it's possible that we might deprecate and eventually remove the constant link type.

- Andrew
--
Dear God, I didn't think orange went with purple until I saw
the sunset you made last night.  That was really cool. - Caro


References:
RE: Initializing a record VAL field with a constant J. Frederick Bartlett

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