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From: REH (spamjunk_at_[hidden])
Date: 2008-04-12 08:36:01

Jurko Gospodnetić wrote:
> Hi REH.
>> Hi. I just started playing with Boost Jam after using ftjam. One thing
>> that I've noticed, that I don't like, it that Boost Jam waits until an
>> action has completed before displaying its output.
>> I have actions that are very time consuming, and I like to monitor their
>> output in real time. ftjam does this, but I would prefer to use Boost,
>> because is has newer features that I want to take advantage of.
>> Is it possible to modify Boost Jam to display actions' output in real-time?
> Would be relatively simple to do (modifications to exec*.c modules
> and possibly output.c), but could you then describe how you expect that
> output to behave in case of multiple parallel build actions (i.e. when
> the -j # command-line options is used with # > 1 )?
> As I see it Boost Jam currently collects each build action output in
> real-time but displays it only once the action has terminated.
> Some ideas that pop to mind here:
> (1.) As it is now - just display action output after the action
> terminates.
> (2.) Display the action as it is collected from each action,
> without considering multiple parallel actions.
> (3.) If there are no parallel actions then as (2.) and otherwise as
> (1.).
> (4.) As (2.) but display the output line-by-line so that lines
> never contain half output text from one action and half from another but
> different lines from multiple actions may get mixed up.
> (5.) As (4.) but give each action an id and display it in front of
> each line in the output. Possibly not displaying the id in case no
> parallel build actions are allowed.
> Anyone else have any other ideas on how this could work? Or which
> choice is best?
> Another related issue is how the action output is collected
> programmatically (i.e. when callbacks containing the action output are
> called). Should that also be done in real-time? Or should that keep
> getting called only after an action has completed its work?
> Since this would affect everyone's build system in ways that I can
> not imagine, I would not like to change anything without enough
> thoughts/comments/confirmation from others... so... if you want
> something done about this - you'll have to keep pushing the issue until
> 'enough' people agree. :-)

Thanks for responding. I don't need parallel builds, so that is not an
issue. I am also not expecting the maintainers of Boost Jam to make this
change. I was planning on just making a local change myself, but I
haven't had time to dig into the code.

Thanks again,


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