Thank you Jeff,
this confirms that I can set 0 in the ca_add_event_array. In any case of epics combinations (ioc, client) that would work properly at monitor receive.
Thanks and best regards
Anton
__________________________________________
Paul Scherrer Institut
Dr. Anton Christian Mezger
WBGB/103
CH-5232 Villigen PSI
Telefon: +41 56 310 34 06
E-Mail: [email protected]
From: Hill, Jeff [mailto:[email protected]]
Sent: Donnerstag, 16. Januar 2014 17:07
To: Mezger Anton Christian; [email protected]
Subject: RE: garbage in zero length arrays
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
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]