You can also use this alternative loop style that will always run at least once:

my $wwn;
do {
  print "Enter the wwn: ";
  chomp ($wwn=<STDIN>);
  my @wwn = unpack ("(a2)*", lc($wwn));
  @wwn = join (":", @wwn);
  print "@wwn\n";  
} until ($wwn eq "q");

[download]

Also, it's confusing that you have @wwn and $wwn. You should consider renaming one.

In reply to Re^2: Getting "un initialized value" error though variable is initialized. Please help. by Anonymous Monk
in thread Getting "un initialized value" error though variable is initialized. Please help. by perl514

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