sed命令

sed命令

在匹配行的前后插入新行，sed的man手册说明如下：

a \行后
text   Append text, which has each embedded newline preceded by a backslash.
i \行前
text   Insert text, which has each embedded newline preceded by a backslash.

示例如下：

行后插入内容：

sed -i "/This is the test line/a\This is the line we inserted." /root/test.txt

行前插入内容：

sed -i "/This is the test line/i\This is the line we inserted." /root/test.txt