I am trying to timeout regex that takes over a second to complete. This alarm does not seem to ever go of. I am some what sure that some of the regex that is used working against large files definatly would take over a second. Can anyone give me a particular regex against a string that would take a long time to complete to test the timeout or tell me what I might be doing wrong . Here is the part of the code that is in question, I am using perl 5.8.7. Thank you. 
eval {
local $SIG{ALRM} = sub { $signal = 'alarm'; die 'alarm'; };
                            alarm(1);
                            @a = ($input =~ /$regex/xg);
                            alarm(0);
};
if ($@ =~ /alarm/  ||$signal eq 'alarm') {
                           $error = "regex match timed out";
                            print "$error\n";
                            die;
                        }

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Update: Regex example given by Hue-Bond sets off the alarm but the regex examples given by Ieronim and wfsp does not. does anyone know what that is the case?

In reply to Timeout alarm for regex by Otogi

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