[Scons-users] intermediate builder step -- wish for no-build when the original files are unch

[Jay Damask]

Dirk Bächle <tshortik <at> gmx.de> writes:


> 

> Hi Jay,

> 

> thanks a lot for your follow-up post. I'll have some more time to look 

> into this tonight. For now I have a rather simple question (see below).

> 

> ...

> 

> "What happens if you start SCons another time, right after the second 

> run and without changing any sources?"

> 

> Is everything up to date then?

> 

> Regards,

> 

> Dirk

> 

> _______________________________________________


Hi Dirk, good morning. 

For the dirty second time and each time following, the intermediate step 
(protoc) is invoked and the timestamps on the *.pb.* files are updated. Its 
the timestamp updates that spoof the code editor into thinking the file is 
updated. 

This leads to another question, which is: what is the best practice to 
observe (user-level) that an Action is invoked? Right now I'm doing an 
env.subst() on the $PROTOC_COM in the _protoc_emitter() fcxn. I found this 
to be an ok proxy, but not precise. An alternative hack that I did was to 
augment the $PROTOC_COM string to include a leading "echo 'action triggered' 
&&", which was duly printing to stdout. 

Thanks, -Jay