Did you already check perlvar?

Look for $. and $\.

But I wonder how you produce values separated with ; (semicolon), when you used , (comma) in your code? ;))

Update: example added: 

#!/usr/bin/perl
# vi:ts=4 sw=4 et:
use strict;
use warnings;

while ( <DATA> ) {
    chomp;
    local $\ = $. % 5 ? ";" : "\n";
    print;
}

__DATA__
1
2
3
4
5
6
7
8
9
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12
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15

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In reply to Re: Concatenate every 5 lines of input with a comma. by linuxer
in thread Concatenate every 5 lines of input with a comma. by jsh

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