打包/解压缩 - 小端 - 64位 - 问题

Question

#!/usr/bin/env perl
use warnings;
use 5.012;

my $var = 1 << 31;
say unpack( "B*", pack( "N", $var )  );

# 10000000000000000000000000000000

如何从

打包/解压缩

my $var = 1 << 63;

这样的输出？

# 1000000000000000000000000000000000000000000000000000000000000000

Answer 1

say unpack("B*", pack( "Q>", $var ));

>强制Q（无符号64位“quad”）类型上的big-endian字节顺序。