's/^[[^0-9]][[^[:space:]]][[^[:space:]]]*[[[:space:]]]*//' 这个有点模糊那个给我讲讲
2017-08-24
ifconfig wlan0 | grep 'inet addr' | sed -r 's/.*:([0-9.]+) .*$/\1/'
2017-07-19
awk -F':' '{ print $1,$3,$4 }' /etc/passwd
2017-07-19