Here's a demonstration - in Perl - that shows you how to avoid a ^C (Control C) dropping you straight out of a program.

Have you ever accidentally hit ^C in the wrong window and terminated a long-running process just before it finished ... well, by setting $SIG{INT} to the address of a sub you want to run, you can divert the signal in Perl. The example code here simulates a long running process with a loop of 60 short sleeps (naps?) ...

$SIG{"INT"} = \&nowayjose;
 
$| = 1;
 
for (1..60){
  print "dot";
  sleep 1;
 
  if ($rq) {
    exit if (time() - $recent < 4) ;
    print "\nNah\n";
    $rq = 0;
    $recent = time();
    }
  }
 
sub nowayjose {
  $rq = 1;
  }

You'll note that all my extra "sub" does is set a flag so that the interrupt can be nicely handled at the end of the loop, that the handler turns the interrupt flag back off, and that I've written the program so that a second ^C within 4 seconds WILL cause it to exit.

As an afterthought ... if you disable ^C completely (i.e. if you don't use the 4 second trick), how will you get out of the program? Well ... you'll still be able to suspend it with ^Z then kill it with kill %1, or you'll be able to find its process id and use a kill -9
(written 2008-12-05, updated 2008-12-07)

 P667 - Perl - Handling Huge Data
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  [762] Huge data files - what happened earlier? - (2006-06-15)
  [975] Answering ALL the delegate's Perl questions - (2006-12-09)
  [1397] Perl - progress bar, supressing ^C and coping with huge data flows - (2007-10-20)
  [1920] Progress Bar Techniques - Perl - (2008-12-03)
  [2376] Long job - progress bar techniques (Perl) - (2009-08-26)
  [2805] How are you getting on? - (2010-06-13)
  [2806] Macho matching - do not do it! - (2010-06-13)
  [2834] Teaching examples in Perl - third and final part - (2010-06-27)
  [3374] Speeding up your Perl code - (2011-07-30)
  [3375] How to interact with a Perl program while it is processing data - (2011-07-31)

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Melksham Oak Community School, Melksham, Wiltshire
Team changes at Well House - looking forward
Flash (client) to PHP (server) - example
Introduction to Object Oriented Programming
Preventing ^C stopping / killing a program - Perl
Making it all worthwhile
Flurinci knows Raby Lae PHP and Jeve
Romeo and Julie
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