Experimental Physics and
Industrial Control System

Michael Davidsaver via Core-talk <core-talk at aps.anl.gov> · Thu, 11 Mar 2021 07:13:13 -0800

On 3/11/21 1:39 AM, Ben Franksen via Core-talk wrote:
> Context: https://github.com/epics-modules/lua/issues/22
> 
>> The string replacement is weird because of how calls to the registered IOC shell functions are executed. I previously had added a function into base that allowed me to query the IOC's function registrar for the functions that had been registered. However, later on, one of the base developers decided that they didn't like the idea of having that access to outside code, so it was removed.
> 
> A very bad decision IMO. Can we please reopen discussion on that?

My objection to iocshFindCommand() as a public API still stands.
I feel it exposes too many details of how iocsh currently works.
Specifically, by exposing the function pointer it prevents this
type from ever being changed.  eg. I'm thinking to add a second,
alternative, form which can return an error, and pass in an extra
void* as context.

I'm open to adding an alternative to iocshCmd() provided it doesn't
close off avenues for future work.  Perhaps passing in an array of
strings?

>> Because that got removed, the way that calling IOC shell functions happens is by constructing a string and calling iocshCmd. iocshCmd is what is processing the string replacements and why it is only happening when calling epics functions.
> 
> You should not be forced to resort to such a horrible kludge.
> 
> Cheers
> Ben
> 

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System