risky_shell

UAB L/K Peter Andersson <>
Thu Dec 2 18:51:28 CET 2004


[...]
> 
> I thought my suggestion to mention the name of the flag in the
> release notes only was quite reasonable.  (-:
> 

Fair enough, but I'd rather not mention it at all. ;-) 


> > The old parallell startup behaviour *could* be useful to
> > start tracing early.
> 
> *Is* useful.
> Feel free to provide a list of *more* useful ways to
> accomplish the same thing.  ;-)
> (I believe this was the main reason why you agreed to
> put it back in...)
> 

Maybe the application could start in two steps: First start a tracer
process (which evaluates a trace config file, for example), then
initiate the main application start sequence.

You could maybe use the -s flag to call a main tracer start function
(again which perhaps evaluates a trace config file). That should switch
on tracing right after erts & kernel, but before your own applications
start. 

If it's not possible for you to have tracing start automatically, but
need the option to call these functions manually from the shell, I agree
there's no simple straightforward way to sync your application with the
shell.

I thought the reason you insisted we put the old behaviour back was that
it was not feasible for you to change the way you are tracing today in
AXD-301, not that this was necessarily the most useful way to accomplish
it.

With my statement I wanted to say to everyone else: "please find other
ways to start tracing of your applications than go experimenting with
the old error prone shell start behaviour, which may even give you
unpredictable results". Not documenting the flag in question is of
course a way of saying the same thing.


[...]
> 
> OK, I didn't really mean to push you to make the feature
> "documented" in the sense that it would encourage people
> to depend on it.
> 
[...]

I see your point. I could - and maybe I should - have documented the
flag as one of those *strongly discouraged* things. But you know,
reintroducing an error (even under somewhat controlled forms) isn't
something to be proud of. I thought I could get away with not saying
anything to anyone, except you. Then you, of all people, give me away!
You'll never get another undocumented flag from me again! :-)

 /Peppe



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