Your code is close but has two problems. First you do not use the g modifier in your regex, so your code runs into an endless loop. Second, your have a typo in this line: 
$authentication .= $authentiction. $1. " ";

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That tells me you are using my but you are not using strict! Remember, always use strict.

If you change that code to 
$authentication .= $authentication. $1. " ";

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all is fine.

That all boils down to 
   while ($str =~/authentication ?(\S+)?/g){
      $authentication .= $authentiction. $1. " "; #more perlish
   }

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or even 
  $authentication = join " ", $str =~ /authentication ?(\S+)?/g; #even
+ more perlish

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holli, /regexed monk/

In reply to Re: Extracting text from a string using regex by holli
in thread Extracting text from a string using regex by ramya2005

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