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<== Date ==> <== Thread ==>
Subject: Re: INP field length
From: Dirk Zimoch <[email protected]>
To: Steve Kinder <[email protected]>
Cc: [email protected]
Date: Tue, 13 Apr 2010 15:26:32 +0200
Hi Steve

I once tested this and found that 78 chars after the @ are possible (after macro expansion). However due to CA limitations you cannot read the link completely with caget.

For ports without addresses (RS232, TCP) you can skip the " 0" address part at the end (saves you 2 chars). Use short names for protocol files, protocol names, port names.

Dirk

Steve Kinder wrote:
Hi Andrew

Thanks for the reply, that was what I thought. But just to clarify my specific case. I'm using StreamDevice2 and have a INP field as follows with template/substitution.

field(INP, "@TEST.protocol getCs($(DEVICE),C2,C3,C4) $(port) 0")

If I understand things correctly, whatever the length of DEVICE and port I shouldn't encounter problems. Well due to the length of the field at least.

Regards

Steve

----- Original Message ----- From: "Andrew Johnson" <[email protected]>
To: <[email protected]>
Cc: "Steve Kinder" <[email protected]>
Sent: Monday, March 15, 2010 3:30 PM
Subject: Re: INP field length


Hi Steve,

On Monday 15 March 2010 04:45:15 Steve Kinder wrote: 
Is there any length restriction on an INP field, before or after the
expansion of any macros it may contain?

Unlike many places inside the IOC, there is no built-in length limitation to
the value that can be placed in a link field using dbLoadRecords(), which
means that the @parm part of a hardware link address can be as long as you
like.

Of course if you want to read or update the field through CA there is a 40
character limit to the string you can pass as a DBR_STRING, and with the new
array-of-chars support in 3.14.11 using the @ field modifier I believe CA will
still limit you to passing at most 72 characters to/from a link field.

HTH,

- Andrew
--
The best FOSS code is written to be read by other humans -- Harald Welte







References:
INP field length Steve Kinder
Re: INP field length Andrew Johnson
Re: INP field length Steve Kinder
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