$argact = $ARGV[0] or die "No number given\n";
open INPUT, 'one.txt' or die $!;
open NEWFILE, '>', 'output' or die $!;
while (<INPUT>){
  if(/^Authentication\s+number\s+is/) {
    my ($old_num) = /(\d+)/;
    if ($argact != $oldnum) {
      $changeflag = 1;
      s/\d+/$argact/;
    }
  }
  print NEWFILE;
}

[download]

Note: I've included $changeflag only because it was in the original code. I've no idea what it's there for. Maybe its value is checked later on in the program.

Update: Typo fixed.

--
<http://dave.org.uk>

"The first rule of Perl club is you do not talk about Perl club."
-- Chip Salzenberg

In reply to Re: File modification by davorg
in thread File modification by madtoperl

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