in reply to Re^7: How to deal with a forked proces that is waiting for user input?
in thread How to deal with a forked proces that is waiting for user input?

Here is the output with no upgrade

C:\Sandbox\AutoPilot\src>perl timedCommand.pl Command timed out after 10 seconds and returned **TIMEOUT** Microsoft DiskPart version 5.1.3565 Copyright (C) 1999-2003 Microsoft Corporation. On computer: USITPAPADGD1C DISKPART> C:\Sandbox\AutoPilot\src>perl timedCommand.pl exit Command returned Microsoft DiskPart version 5.1.3565 Copyright (C) 1999-2003 Microsoft Corporation. On computer: USITPAPADGD1C DISKPART> Leaving DiskPart... C:\Sandbox\AutoPilot\src>perl cd Can't open perl script "cd": No such file or directory C:\Sandbox\AutoPilot\src>perl timedCommand.pl cd Command returned C:\Sandbox\AutoPilot\src

Seems like it is the same as on your system, which is good because upgrading to the newer thread would not be a suitable solution for other people.

I have a question on your implementation, lets say I wanted to every 5 seconds check the entries in @results, to see if the last entry matches a certain regex, and that the size of @results hasn't changed. How would you do this? I was able to figure out how using the queue

That being said I have been playing around with the code I was working on and seem to have a solution that works using queues.

Here is how I did it:

my $queue = new Thread::Queue; my $command = 'diskpart'; my $status = _timedCommand($command, 90); if ($status eq 'TIMEOUT') { print "\n=======TIMEOUT==========\n"; } my @ans; while (my $ref = $queue->dequeue_nb()) { if (ref($ref) =~ m/ARRAY/i) { push(@ans, @$ref); } else { push(@ans, $ref); } } print "@ans\n"; sub _timedCommand { my ($command, $time) = @_; my $pid :shared; my $thr = async { $pid = open my $fh, "$command |" or die "$!"; while (<$fh>) { $queue->enqueue($_); } close($fh); }; while ($thr->is_running() and $time > 0) { sleep(1); $time--; #Special Case Checking, if we get to 30 seconds #check to see if we might be waiting on user input if ($time == 30) { #only check once give it time my $num = $queue->pending(); if ($num > 100) { #if we have a lot of entries, then its #most likely not an input hang next; } print "Num Pending $num\n"; for (my $i=0; $i < $num; $i++) { my $line = $queue->[$i]; #Check DiskPart: if ($line =~ m/^Microsoft DiskPart/i) { #If we are hung up waiting for user input #the second to last line in the queue will #be On Computer: check for it if ($queue->[$num-2] =~ m/^On Computer:/i) { $time = 0; last; } } #End DiskPart Check } } } if ($thr->is_joinable()) { $thr->join(); return 'OK'; } else { kill 3, $pid; $thr->join(); return 'TIMEOUT'; } }

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Re^9: How to deal with a forked proces that is waiting for user input?
by BrowserUk (Patriarch) on Oct 22, 2008 at 18:13 UTC

      Fair enough. I just thought it would be a nice improvement, but its not absolutely needed.

      Separate from the the matching portion of the code do you see any issues with the implementation I have using queues?

      Thanks for all your help, I appreciate a great deal.