Maybe you could do this: read all user lines, find the largest id, increment it for the user being added. 
#! perl -w
use strict;

my @users = grep /[^\s]+/, <DATA>;

my $max = 0;
$max = $_ > $max ? $_ : $max for map { /(\d+)|/; $1 || 0 } @users;

++$max;
push @users, "$max|Rudif|scribe\n";

print for @users;

__END__

1|Title|Description
3|Title|Description
4|Title|Description

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Rudif

In reply to Re: Storing Info in a text File by Rudif
in thread Storing Info in a text File by Anonymous Monk

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