All you need to use is the auto-increment operator. 
$a = 'A000001';

while (1) {
    print "$a\n";
    $a++;
}

[download]


look up the ++ operator in perlop under Auto-increment.

Also you should avoid the <> operator for <STDIN> unless you want the side-effects. merlyn explains it better than I.

UPDATE: If you want, take a look at a fun use of auto-increment.

OR 
$a = 'A000000';
while (1) { print $a++,"\n"; }

[download]


grep
grep> cd pub
grep> more beer

In reply to Re: make a counter by grep
in thread make a counter by agustina_s

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