This will create output files split1 through split4. They will vary slightly in size in order that each file contains complete lines. The memory usage is minimal: 

#! perl -sw
use strict;

open I, '<', $ARGV[0] or die $!;
seek I, 0, 2;
my $n = int( tell( I ) / 4 );
seek I, 0, 0;

my $s = $n;
for my $i ( 1 .. 4 ) {
    open O, '>', "split$i" or die $!;
    while( tell( I ) < $s ) {
        print O scalar <I>;
    }
    $s += $n;
    close O;
}
__END__
C:\test>dir words.txt
17/07/2011  15:52         1,941,858 words.txt

C:\test>split4 words.txt

C:\test>dir split*
08/02/2013  00:41           485,470 split1
08/02/2013  00:41           485,458 split2
08/02/2013  00:41           485,468 split3
08/02/2013  00:41           485,462 split4
08/02/2013  00:38               298 split4.pl

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With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
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In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re: Split file into 4 smaller ones by BrowserUk
in thread Split file into 4 smaller ones by Anonymous Monk

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