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Message-ID: <530FCFB08F31D411A47F009027D5D01F01127C76@conan.esr.hp.com>
From: "Halim, Salman" <salman@Bluestone.com>
To: "'ant-dev@jakarta.apache.org'" <ant-dev@jakarta.apache.org>
Subject: RE: exec in thread
Date: Fri, 20 Apr 2001 13:25:15 -0400
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that's what i was thinking, too; i was thinking of either tweaking the exec
task to accept a "background=true" (false by default so as to not conflict
with existing scripts) attribute that would prepend a "start" or the
"/bin/sh" (with "&" appended), depending on the os.

then, i thought, what if i use a simple launcher which calls ant with a
-DcommandStart="/bin/sh -c" -DcommandEnd="&" on unix and "start" and "",
respectively, on windows and just change all my commands to start with
${commandStart} as the executable and ${commandEnd} as the very last part.
need to look into this, though i have a feeling the unix variant being two
words will require a bit more tweaking.

thoughts?

-- 
Salman Halim
Advisory Software Engineer, HP Bluestone
Quidquid latine dictum sit, altum viditur.


-----Original Message-----
From: Jose Alberto Fernandez [mailto:j_a_fernandez@yahoo.com]
Sent: Friday, April 20, 2001 12:05 PM
To: ant-dev@jakarta.apache.org
Subject: RE: exec in thread


I have had simillar kinds of needs and would also like some way to achieve
it. In my case I wanted to use it for starting server processes, e.g.,
tomcat servers that must stay running in the background.

For example to run tests, I need to have the servers running first and only
then can I dispatch things to it. I do not want the servers to go up and
down all the time.

We could do such things using the "start" command on NT and "/bin/sh -c ...
&" on UNIX, do not know about other systems.

Any ideas?

Jose Alberto

> -----Original Message-----
> From: Halim, Salman [mailto:salman@Bluestone.com]
> Sent: Friday, April 20, 2001 4:21 PM
> To: 'ant-dev@jakarta.apache.org'
> Subject: RE: exec in thread
>
>
> i appreciate your response.  thank you.
>
> i understand what you're saying about possible
> synchronization or deadlock
> issues with a parallel execution.  my intention is to start a
> process that
> will keep running long after the ant build is done.
> basically, i'm not
> using ant to install anything, per se.  i'm using ant's
> platform independent
> way of specifying environment variables to basically act as a
> launcher that
> will allow me to launch a process on both windows and unix
> using just this
> one configuration file.  (rather than having a windows batch
> file AND a
> separate unix shell script:  two things to maintain.  this is
> what we have
> right now.)
>
> i had initially toyed with the idea of writing a (much
> simpler) application
> from scratch that would basically accept an xml file
> describing environment
> variable settings, things to launch, whether to do it in the
> background etc.
> and would then generate both windows batch files as well as unix shell
> scripts from that.  however, i figured using ant would allow
> me to NOT have
> to do all that coding by hand :) even though ant wasn't
> necessarily designed
> for the task.
>
> what i need to be able to do is start more than one process,
> each running in
> parallel (otherwise, i have nothing against letting the ant
> "build" keep
> running).
>
> any thoughts on this approach would be appreciated.
>
> thanks again!
>
> --
> Salman Halim
> Advisory Software Engineer, HP Bluestone
> Quidquid latine dictum sit, altum viditur.
>
>
> -----Original Message-----
> From: Conor MacNeill [mailto:conor@cortexebusiness.com.au]
> Sent: Friday, April 20, 2001 10:52 AM
> To: ant-dev@jakarta.apache.org
> Subject: Re: exec in thread
>
>
> Salman,
>
> A couple of issues. I understand this is incomplete and there
> are therefore
> some issues you have yet to encounter.
>
> Firstly, we have been discussing supporting parallel
> execution of tasks
> within a target. This will satisfy a number of needs to
> either run test
> harnesses against servers or to better utilise powerful
> hardware during a
> build. A possible expression might be
>
> <target>
>    <parallel>
>        <javac>
>        <javac>
>    </parallel>
> </target>
>
> Now, that is not quite what you are proposing - you are basically just
> running the thread and forgetting about it - you don't join
> to that thread
> again. Rather than tackle this for the particular task
> (exec), this could
> be approached as
>
> <target>
>     <daemon>
>         <exec>
>     </daemon>
> </target>
>
> Thus any task could be run in the background and not just
> exec. I think,
> however, we need to think carefully about the implications of threads
> running while ant continues to run. If the thread continues
> to interact
> with Ant there may be synchronization or deadlock issues.
> Also the thread
> may keep the Ant VM alive when Ant itself has finished.
>
> Anyway, if you continue to go with your task, I think one
> issue you will
> encounter is the management of the output of the exec task
> and connecting
> that into Ant's event mechanism.
>
> Conor
>
>
>
>
> ----- Original Message -----
> From: "Halim, Salman" <salman@Bluestone.com>
> To: <ant-dev@jakarta.apache.org>
> Sent: Saturday, April 21, 2001 12:05 AM
> Subject: FW: exec in thread
>
>
> > hi,
> >
> > i didn't recieve a response last time so i'm trying again. . .  any
> advice
> > is appreciated.  thank you!
> >
> > --
> > Salman Halim
> > Advisory Software Engineer, HP Bluestone
> > Quidquid latine dictum sit, altum viditur.
> >
> >
> > -----Original Message-----
> > From: Halim, Salman [mailto:salman@Bluestone.com]
> > Sent: Tuesday, April 17, 2001 3:56 PM
> > To: 'ant-user@jakarta.apache.org'; 'ant-dev@jakarta.apache.org'
> > Subject: exec in thread
> >
> >
> > hi,
> >
> > i have the attached MyExec class; this is supposed to be a primitive
> > replacement for the exec task that will run its target in
> the background
> (by
> > spawning a thread and running in there).  it isn't complete
> yet, but i
> > wanted to do some testing before going any further:
> >
> > in short, the thread doesn't continue to run once the main
> class is done.
> > if i uncomment the delay loop in there, then it runs
> (because the main
> > MyExec is still running).
> >
> > can anybody see if i'm doing something anti-ant in there,
> please?  this
> > class is not very complicated, i promise!
> >
> > thank you in advance,
> >
> > --
> > Salman Halim
> > Advisory Software Engineer, HP Bluestone
> > Quidquid latine dictum sit, altum viditur.
> >
> >
> >
> >
>