Experimental Physics and
Industrial Control System

"Chestnut, Ronald P." <[email protected]> · Wed, 9 Sep 2009 10:54:26 -0700

Mr. Expedient here.

With any luck, all the code in the sequencer uses MACRO_STR_LEN, and a change to something larger but static (perhaps 61 or 100?) might just work after a recompile. Doing something dynamic requires actual thinking and more extensive testing. How about an initial static bump with a subsequent dynamic solution?

Ron Chestnut 

-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of Eric Norum
Sent: Wednesday, September 09, 2009 6:15 AM
To: [email protected] Techtalk
Subject: Re: sequencer feature request

Mr. Small IOC here.
Rather than allocating the maximum-sized space for every single name,  
why not expand the name into a 'big-enough' buffer and then allocate  
only the required size and copy the result?

On Sep 9, 2009, at 5:13 AM, Dirk Zimoch wrote:

> I found several places in the code where the sequencer uses  
> MAX_STRING_SIZE+1 for string lengths of PV names and macros. In  
> EPICS base MAX_STRING_SIZE is defined as 40. For example in  
> seq_main.c:
>
> /*
> * Evaluate channel names by macro substitution.
> */
> #define		MACRO_STR_LEN	(MAX_STRING_SIZE+1)
> LOCAL void seqChanNameEval(pSP)
> SPROG		*pSP;
> {
> 	CHAN		*pDB;
> 	int		i;
>
> 	pDB = pSP->pChan;
> 	for (i = 0; i < pSP->numChans; i++, pDB++)
> 	{
> 		pDB->dbName = calloc(1, MACRO_STR_LEN);
> 		seqMacEval(pDB->dbAsName, pDB->dbName, MACRO_STR_LEN, pSP->pMacros);
> #ifdef	DEBUG
> 		printf("seqChanNameEval: \"%s\" evaluated to \"%s\"\n",
> 			pDB->dbAsName, pDB->dbName);
> #endif	/*DEBUG*/
> 	}
> }
>
> It might help to replace those uses of MAX_STRING_SIZE+1 with  
> PVNAME_STRINGSZ.
>
> Dirk
>
>
>
> Dirk Zimoch wrote:
>> I tested the sequencer with a long name and it seems that it  
>> truncates the PV name to 41 chars.
>> A seqChanShow shows the difference between the name used in assign  
>> and the actual name used in CA:
>> Channel name: "DZ:45678901234567890123456789012345678901"
>>  Unexpanded (assigned) name: "DZ: 
>> 456789012345678901234567890123456789012345678901234567890"
>> Dirk
>> Mark Rivers wrote:
>>> EPICS base defines the maximum length of the PV name to be  
>>> PVNAME_STRINGSZ, which is currently 61 including the nil terminator.
>>> What length limitation does the sequencer impose?  Is it more  
>>> restrictive than this?
>>> Mark
>>>
>>> ________________________________
>>>
>>> From: [email protected] on behalf of Patrick Thomas
>>> Sent: Thu 9/3/2009 6:29 PM
>>> To: [email protected]
>>> Subject: sequencer feature request
>>>
>>>
>>>
>>> Hi,
>>>
>>> I was wondering if I could ask for a feature request for the next
>>> version of the sequencer? Is there any chance that it would be  
>>> possible
>>> to use unlimited length record names in assign to statements?
>>>
>>> Thank you,
>>> Patrick
>>>
>>>
>>>
>>>
>
> -- 
> Dr. Dirk Zimoch
> Paul Scherrer Institut, WBGB/006
> 5232 Villigen PSI, Switzerland
> Phone +41 56 310 5182

-- 
Eric Norum <[email protected]>
Advanced Photon Source
Argonne National Laboratory
(630) 252-4793

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System