Re: Dynamic Loading and Unloading of EPICS Device Support and Record.

[Marty Kraimer <mrkraimer@comcast.net>]

 On 09/08/2010 04:09 PM, Ben Franksen wrote:
> On Mittwoch, 8. September 2010, Eric Norum wrote:
> > What's the use case for this, anyhow?
> Yes, I would be interested in that, too.
The following is not for an embeded system but does show a good use for 
on-line add and delete.
Guabao Shen (BNL) is developing a "gather" service. The service uses a 
javaIOC. The javaIOC has gather records. Each gather record collects 
data from a set of caV3 records and provides the result to the client as 
an array.
The javaIOC also has a createGather record. The client supplies a list 
of channels to the createGather record. When the record processes it 
creates and installs a new gather record. The gather record can be 
temporary or permanent. If the record is temporary than after no clients 
are attached to the record for some fixed period of time the gather 
record is automatically deleted. If it is permanent it can be deleted by 
request.
Both on-line add and delete are required in other for this to be a 
robust service.