最赞回答 / 渐入佳境coder
awk 'ARGIND==1{A[$0]} ARGIND>1&&!($0 in A){print $0}' file1.txt file2.txt
2017-10-20
ifconfig eth2 |sed -n '/inet /p'|sed 's/^.*r:\(.*\)B.*$/\1/'
2017-10-16