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Setting a timer to a system call

by Freezer (Sexton)
on Aug 15, 2012 at 15:17 UTC ( #987568=perlquestion: print w/replies, xml ) Need Help??

Freezer has asked for the wisdom of the Perl Monks concerning the following question:

Dear Monks,

I have a system call from within Perl to a Java program. I would like to set it up so that if the Java program does not finish executing within a fixed period of time it times out.

I was thinking of using a Linux call something like:
ulimit -t 200 | java ....
Although this does not throw an error, it clearly does not do what I want it to do.

Does anyone have potential solutions?

Replies are listed 'Best First'.
Re: Setting a timer to a system call
by zentara (Archbishop) on Aug 15, 2012 at 15:38 UTC
      I think that this code you link to looks interesting. However, oh so complicated. Is it worth reflecting on how other languages might handle this problem, as it seems that a new Perl command could be in order?
        It dosn't get much simpler than this. Instead of the SIG(INT), you could just directly call exit, for a quicker kill.
        #!/usr/bin/perl -w use strict; use threads; use threads::shared; my $timer_go:shared = 0; my $worker = threads->create(\&worker); my $timer = threads->create(\&timer,$worker); print "hit enter to start\n"; <>; $timer_go=1; <>; $timer->join(); $worker->join(); sub timer { my $worker = shift; while(1){ if($timer_go){ my $count = 0; while(1){ $count++; if($count > 5){ print "timed out\nHit enter to finish\n"; # Send a signal to a thread $worker->kill('INT'); return; } sleep 1; print "timing $count\n"; } }else{sleep 1} } } sub worker { $|++; $SIG{INT} = sub{ warn "Caught Zap!\n"; sleep 1; exit; }; # do your timed program here. my $worker_pid = open( READ, "top -d 1 -b |" ); print "\t$worker_pid\n"; while(<READ>){ } return; }

        I'm not really a human, but I play one on earth.
        Old Perl Programmer Haiku ................... flash japh
Re: Setting a timer to a system call
by runrig (Abbot) on Aug 15, 2012 at 15:42 UTC

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