$ perl -E '
> say q{Big-endian};
> $BEflag = pack q{N}, 1;
> say unpack q{B*}, $BEflag;
> say sprintf q{0x%02x}, ord $_ for split m{}, $BEflag;
> say unpack q{N}, $BEflag;
> say q{Little-endian};
> $LEflag = pack q{V}, 1;
> say unpack q{B*}, $LEflag;
> say sprintf q{0x%02x}, ord $_ for split m{}, $LEflag;
> say unpack q{V}, $LEflag;'
Big-endian
00000000000000000000000000000001
0x00
0x00
0x00
0x01
1
Little-endian
00000001000000000000000000000000
0x01
0x00
0x00
0x00
1
$