#!/usr/bin/perl -w
use strict; ### a must

my $parts = shift; ### how many parts to split
my @file = @ARGV;  ### the files to split

foreach ( @file ) {

  ### how big should the new file be?
  my $size = -s $_;
  my $buf_size = $size / $parts;

  ### ready a buffer for the data
  my $buf = '';

  ### open the input file
  open ( In, $_ ) ||
    warn "Cannot read $_: $!\n";
  binmode ( In );

  ### for as many parts as there are, read
  ### the amount of data, then write it to
  ### the appropriate output file.
  for ( my $i = 0; $i < $parts; $i++ ) {

    ### read an output file worth of data
    read ( In, $buf, $buf_size ) ||
      warn "Read zero bytes from $_!\n";

    ### write the output file
    open ( Out, "> $_$i" ) ||
      warn "Cannot write to $_$i: $!\n";
    print Out $buf;

    ### if this is the last segment,
    ### grab the remainder
    if ( $i == ( $parts - 1 ) ) {
      my $rem = $size % $buf_size;
      if( $rem ) {
        read ( In, $buf, $rem ) ||
          warn "Read zero bytes from $_!\n";
        print Out $buf;
      }
    }

    ### we are done with the current output file
    close ( Out );
  }

  ### we're done spliting the input file
  close ( In );
}

exit;