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

Subject: RE: garbage in zero length arrays
From: "Hill, Jeff" <[email protected]>
To: Mezger Anton Christian <[email protected]>, "[email protected]" <[email protected]>
Date: Thu, 16 Jan 2014 16:07:28 +0000

 

Ø  My question is: when specifying 0, how does that behave in older epics versions and channel

Ø  access gateways. Does it use then the maximum amount of elements ?

 

When a channel connects the maximum number of elements is supplied by the server as a channel attribute. In newer versions of EPICS the current number of elements is returned with each subscription update. In older versions the maximum number of elements was always returned; when the current number of elements was less than the maximum number then any additional elements at the end were zero padded.

 

Jeff

 

 

From: [email protected] [mailto:[email protected]] On Behalf Of Mezger Anton Christian
Sent: Thursday, January 16, 2014 4:46 AM
To: [email protected]
Subject: garbage in zero length arrays

 

Hi all,

 

When monitoring a non initialized char array with ca_add_event_array, one gets most of the time in the first element of the array.

 

This only when the request uses ca_element_count(chid) which is non zero. When using the dynamic behavior by specifiying 0 elements, the received args.count correspond to the actual size of the array, including zero when not initialized.

 

My question is: when specifying 0, how does that behave in older epics versions and channel access gateways. Does it use then the maximum amount of elements ?

 

Anton

 

__________________________________________
Paul Scherrer Institut
Dr. Anton Christian Mezger
WBGB/103
CH-5232 Villigen PSI

Telefon: +41 56 310 34 06
E-Mail: [email protected]


Replies:
RE: garbage in zero length arrays Mezger Anton Christian
References:
garbage in zero length arrays Mezger Anton Christian

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