Crypt::CipherSaber (similar to what JMD mentioned) allows you to encrypt or to decrypt to and from filehandles. It'd be as simple as: 
use Crypt::CipherSaber;

my $cs = Crypt::CipherSaber->new('Your secret key here');

open(IN, 'mysqldump.sql') or die "Can't open infile: $!";
open(OUT, '>mysqldump.cs1') or die "Can't open outfile: $!";

# depending on your platform
binmode(INFILE);
binmode(OUTFILE);

$cs->fh_crypt(\*INFILE, \*OUTFILE, 1);

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In reply to Re: Encrypting Largish Files by chromatic
in thread Encrypting Largish Files by filmo

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