结果 zhonghua123:x:0:0:root:/root:/bin/bash
[root@bogon data]$sed ‘s/‘‘‘$var‘‘‘/zhonghua123/g‘ /etc/passwd
[root@bogon data]$sed ‘s/‘‘‘$var‘‘‘/&123/g‘ /etc/passwd
root123:x:0:0:root123:/root123:/bin/bash
2258 i686
3122 noarch
4639 x86_64
[root@bogon Packages]$ls .rpm |sed -r ‘s#..(.*).rpm$#\1#‘|sort|uniq -c --使用sed 统计
2258 i686
3122 noarch
4639 x86_64
原文:https://blog.51cto.com/12246080/2473186