安装libpcap出现：
1：error: Your operating system's lex is insufficient to compile
libpcap. ex is a lex replacement that has many advantages, including
being able to compile libpcap.
需要更新lex
执行命令:

sudo apt-get install flex

2：出现错误

yacc -d grammar.y
make: yacc：命令未找到
make: *** [grammar.c] 错误 127

需要安装yacc
inux下是用flex和bison来分别代替lex和yacc的，安装直接使用命令：

sudo apt-get install bison