为什么我得到错误的答案/值？
它应该打印的正确值是1,21775,4但是我总是得到1,3,0？
my $data = pack ('C*',map hex,split /\s+/,"01 00 00 00 7F 08 03 00 21 04 80 04 FF D7 FB 0C EC 01 44 00 61 1D 00 00 10 3B 00 00 FF D7 FB 0C 00 00 8C 64 00 00 EC 45");
($obj->{Version},$obj->{res1},$obj->{EARFCN},$tmp1,$obj->{res2},$tmp2)=unpack("C C3 v C C V",$data);
$obj->{band} = ($tmp1 & 0xfc) >> 2;
print "\n".$obj->{Version}; # Should print 1
print "\n".$obj->{EARFCN}; # Should print 2175
print "\n".$obj->{band}; # Should print 4. Note: this is the first 6 bits from MSB of $tmp1.
print "\n";
解决方法
调试输出：
DB<1> $data = pack ('C*',"01 00 00 00 7F 08 03 00 21 04 80 04 FF D7 FB 0C EC 01 44 00 61 1D 00 00 10 3B 00 00 FF D7 FB 0C 00 00 8C 64 00 00 EC 45")
DB<2> x unpack("C C3 v C C V",$data)
0 1
1 0
2 0
3 0
4 2175
5 3
6 0
7 75498529
模式C3输出三个无符号字节,而不是长度为三的字符串.
我想你想要a3.见Perldoc pack()