Try this (I was bored:):
#! perl -slw
use strict;
our $BUFN //= 1024; $BUFN *= 4096;
our $SIG //= '68 64 76 64 00 00 00 11 64 61 74 61 00 00 00 15 00 00 0
+0 00 02 00 00 00';
$SIG =~ tr[ ][]d;
$SIG = pack 'H*', $SIG;
open my $in, '<:raw', $ARGV[0] or die $!;
my( $offset, $buffer ) = ( 0, '' );
while( sysread( $in, $buffer, $BUFN, length $buffer ) ) {
my $pos = 1+index( $buffer, $SIG );
if( $pos ) {
print "Found signature at offset: ", $offset + $pos - 1;
exit;
}
$offset += length( $buffer ) - length( $SIG );
$buffer = substr $buffer, - length $SIG;
}
close $in;
print "Signature not found";
__END__
02/02/2015 15:42 10,737,418,241 big.csv
C:\test>junk71 -BUFN=4096 -SIG="52 5f d7 58 22 0d 0a 61 68 73 68 77 65
+ 2c 38 30 33 37 31 37 38 35 2c 46" big.csv
Found signature at offset: 1073741817
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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