Re: streamDevice trick for in with or without value

[Dirk Zimoch <dirk.zimoch@psi.ch>]

Hello Emmanuel,

I am sorry but at the moment I do not have any "number or nothing" matching.

But there is still hope: Write your own format converter!
Start with a copy of StdLongConverter from StreamFormatConverter.cc, 
modify it to set value to 0 on failure and return 0. Then register it 
with any unused conversion character. In parse() don't use 
info.append(fmt.conv), use info.append('d') instead.

You are not the first one with such a problem.
Maybe I should extend the syntax to something like %?d to return 0 (and 
succeed) if nothing can be read. Let me see if I can do that quickly.

Dirk



emmanuel_mayssat@lynceantech.com wrote:
> I am using stream.
> I have a serial device whose query/reply follow thisi pattern:
>
> out "get value"
> in  "F: W: IK:"
> If values are 0
>
> If values are not 0, I have
> out "get value"
> in  "F: 12 W: IK:" <- value is 12
>
> Is there a way to make this value conditional in stream?
> With the current protocol, I have a mismatch and my record becomes invalid
> (and stop processing).
>
> 1/ How can I make the protocol work?
> 2/ Assuming that there is a mismatch, how can I restore my record to "valid" status?
>
> thanks,