open BINFILE, "<", "somefile.txt" or die $!;
ReadBytes( $num, \*BINFILE );

sub ReadBytes {
    my ( $num, $binfile ) = @_;
    return undef if $num < 1;
    my @bytes;
    for (1..$num) {
        my $byte;
        read($binfile, $byte, 1);
        push @bytes, unpack("C",$byte);
    }
    return @bytes;
}