RE: Write permission of a record

["Zhang, Tong via Tech-talk" <tech-talk at aps.anl.gov>]

Thanks Andrew, that’s exactly what I wanted! DISP will make my record naturally function read-only.

Also thanks go to Ned and Kay. Yes the ASG is also used as a global management approach for the access permissions.

 

Cheers,

Tong

 

From: Andrew Johnson <anj at anl.gov>
Sent: Monday, August 1, 2022 16:07
To: Zhang, Tong <ZhangT at frib.msu.edu>; tech-talk at aps.anl.gov
Subject: Re: Write permission of a record

 

[EXTERNAL] This email originated from outside of FRIB

Hi Tong,

There is a field in every record type called DISP (Disable Put) which, when set to a non-zero value, prevents any other field of that record from being written to over Channel Access or PV Access. You can still write to the DISP field remotely though, and it doesn't prevent DB links from other records in the same IOC from changing any record fields though, so it might not be quite what you're after but it's pretty close.

- Andrew

On 8/1/22 2:50 PM, Zhang, Tong via Tech-talk wrote:

Hi,

 

I know that channel access security can control the record write permission based on a wide range of rules, but I’m wondering if EPICS has some other way to control the write permission of a record generally from the record definition level? To make it clearer, I would hope there is some field could be used to define the record as ‘read-only’, that is all external CA put request should be denied, the data only could be updated through the internal device support.

 

Thanks,

Tong

-- 

Complexity comes for free, Simplicity you have to work for.