Use a counter! Set $/ to "#" to read the desired chunks. 

use strict;
use warnings;
my $keep = 3;
local $/="#";
while(<DATA>){
    last unless $keep--;
    print;
}
__DATA__
1
#
2
#
3
#
4
#
5

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In reply to Re: Keep only X number of entries of a file using a delimeter by hdb
in thread Keep only X number of entries of a file using a delimeter by Anonymous Monk

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