Dear monks,

I just installed Activestate Perl 5.8 Beta Built 802 under Win2k and played around a bit with threads. Due to the good tutorial at YAPC::Europe everything worked fine...

Then I got a bad idea; i remembered an old DOS program which waited for an input for n seconds, and if it didn't come within those n seconds, it continued with a standard value. I forgot its name, but maybe you know it. Well, might be possible doing so by using threads, I thought...

Here are some lines of code: 

#! /usr/bin/perl
use 5.008;
use strict;
use warnings;
use threads;
use threads::shared;
 
our $Input : shared = "";

sub getInput {
    print "Please enter some- or nothing: ";
    my $input = <STDIN>; chomp($input);
    $Input = $input if defined $input; # or whatever...
}

my $oldInput = $Input;

my $inputThread = threads->create('getInput');

sleep 5;
unless ($Input eq $oldInput) {
    $inputThread->join();
    print "Input was: $Input\n";
    sleep 2;
}
else {
    print "Continuing with 'abcd' as a standard value...\n";
    # WHAT CAN I DO HERE ?
    
}

[download]
Well, my problem is how to get rid off the blocked thread if the user doesn't enter anything... If I run $inputThread->join, the program will block forever. If I run $inputThread->detach() (or do nothing), I will at least be able to continue with my main program, but have got a blocked thread somewhere, and if a user enters anything later, it might give strange results because the shared Variable $Input suddenly has got another value.

Do you know how to solve this problem? (It is not a production problem, but I'm very interested if and how this can be done with threads; well, with fork it wouldn't be a big problem...)

Best regards,
perl -e "s>>*F>e=>y)\*martinF)stronat)=>print,print v8.8.8.32.11.32"

In reply to "killing" perl5.8-threads by strat

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