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Re: How to end "do" with Ctrl-C

by pfaut (Priest)
on Dec 02, 2008 at 22:33 UTC ( #727508=note: print w/ replies, xml ) Need Help??

in reply to How to end "do" with Ctrl-C

You need to trap the INT signal.

our $stopit = 0; $SIG{INT} = sub { $stopit++; }; while (!$stopit) { system("netstat -an | grep $line"); sleep 10; }
90% of every Perl application is already written.

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Re^2: How to end "do" with Ctrl-C
by kennethk (Monsignor) on Dec 02, 2008 at 23:03 UTC
    Yeah, what pfaut said. As an additional note, your chomp removes the end line, so your test would always pass. If you really want to catch bad input, you could try:
    use strict; my $port = shift; our $stopit = 0; $SIG{INT} = sub { $stopit++; }; if (!$port or $port =~ /\D/) { print "usage: program port_num\n"; } else { while (!$stopit) { print system("netstat -an | grep $port"), "\n"; sleep 10; } }

    or whatever variant will get you what you want.

      Thank you, works great!

      print system("netstat -an | grep $port"), "\n";

      That should be

      system("netstat -an | grep $port");


      print qx{netstat -an | grep $port};


      print grep /$port/, qx{netstat -an};

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