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

Subject: Re: PV / record name length
From: Andrew Johnson <anj@aps.anl.gov>
To: <tech-talk@aps.anl.gov>
Date: Fri, 28 Jul 2017 12:11:20 -0500
Correction & better explanation:

On 07/28/2017 12:04 PM, Andrew Johnson wrote:
> On 07/28/2017 11:51 AM, Till Straumann wrote:
>> I see that some places (e.g., dbAccess.c: getLinkValue()) impose a limit
>> of MAX_STRING_SIZE (still 40).
>> How does that play with the PVNAME_STRINGSZ of 61 (base 3.15.5) ?
> 
> The use of MAX_STRING_SIZE in dbAccess.c: getLinkValue() is not related
> to the PV name length, it's just that a DBF_STRING type is (and will
                                        ^^^^^^^^^^^^^^^^^
    s/ a DBF_STRING type / calling dbGet() with dbrType=DBR_STRING /

> probably always have to be) fixed at 40 characters. You can use a
> DBR_CHAR array type to get strings of any length through the dbAccess
> dbGet() API, it does correctly adjust for any length of the underlying
> DBF_STRING field (e.g. CALC fields are currently 80 chars).
> 
> - Andrew
> 
>> On 07/28/2017 08:44 AM, Ralph Lange wrote:
>>
>>> Since this may break existing IOCs, I do not expect your suggestion to
>>> be accepted into upstream Base easily.
>>>
>>> Allowing record names of arbitrary length (i.e. allocated) would not
>>> increase memory consumption for existing installations, but needs a
>>> lot more drastic code changes in crucial places of Base, of course.
> 
> +1
> 

-- 
Arguing for surveillance because you have nothing to hide is no
different than making the claim, "I don't care about freedom of
speech because I have nothing to say." -- Edward Snowdon

References:
PV / record name length Sebastian Marsching
RE: PV / record name length Mark Rivers
Re: PV / record name length Sebastian Marsching
Re: PV / record name length Ralph Lange
Re: PV / record name length Till Straumann
Re: PV / record name length Andrew Johnson

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