github参数解释：https://github.com/irontec/sngrep/wiki#command-line-arguments
Linux 用户可以向 sngrep 添加捕获权限
setcap 'CAP_NET_RAW+eip' /usr/local/bin/sngrep
setcap 'CAP_NET_RAW+eip' $(which sngrep)
为tcpdump设置操作权限：
chgrp pcap /usr/sbin/tcpdump
setcap cap_net_raw,cap_net_admin=eip $(which tcpdump)
