I hope you use strict and warnings? Did you debug? 
1 - # think its a bad idea to start
2 - # with a false value here
3 - $n=0;
4 -
5 - open(OUT,">$n.out");
6 -
7 - while(<>) { #where do you read from really?
8 -    print OUT;
9 -
10-    # that doesn't match anything,
11-    # it will always return true
12-    if (/foo/) {
13-    # why do you do that? use a sub that returns
14-    # a filehandle (or a reference to it)
15-    close(OUT); 
16-    $n++;
17-    open(OUT,">$n.out");
18-    }
19- }
20- close(OUT);
21

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Have a nice day
All decision is left to your taste

In reply to Re: Parsing large files by little
in thread Parsing large files by Spica

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