Question

我需要使用sed将每个匹配的两行模式替换为三行模式。这是我的输入文件（tempfile.txt）。

lease 192.168.6.100 { binding state free; hardware ethernet 00:e0:4c:68:00:96; } lease 192.168.6.100 { binding state active; hardware ethernet 00:e0:4c:68:00:96; client-hostname "andrew-H81M-S2PH"; } lease 192.168.6.100 { binding state free; hardware ethernet 00:e0:4c:68:00:96; } lease 192.168.6.100 { binding state active; hardware ethernet 00:e0:4c:68:00:96; client-hostname "andrew-H81M-S2PH"; }

基本上，如果是client-hostname "HOSTNAME"; 如果缺少，则应使用tab替换为newline。

我的尝试： sed 'N; /hardware.*}/d; P; D' tempfile.txt

结果是：

lease 192.168.6.100 { binding state free; lease 192.168.6.100 { binding state active; hardware ethernet 00:e0:4c:68:00:96; client-hostname "andrew-H81M-S2PH"; } lease 192.168.6.100 { binding state free; lease 192.168.6.100 { binding state active; hardware ethernet 00:e0:4c:68:00:96; client-hostname "andrew-H81M-S2PH"; }

这是我想要的输出。

lease 192.168.6.100 { binding state free; hardware ethernet 00:e0:4c:68:00:96; <tab> } lease 192.168.6.100 { binding state active; hardware ethernet 00:e0:4c:68:00:96; client-hostname "andrew-H81M-S2PH"; } lease 192.168.6.100 { binding state free; hardware ethernet 00:e0:4c:68:00:96; <tab> } lease 192.168.6.100 { binding state active; hardware ethernet 00:e0:4c:68:00:96; client-hostname "andrew-H81M-S2PH"; }

正如您所看到的，在曲线之间始终存在三条线。这就是我的目标。

Answer 1

这样可以解决问题（管道cat -A显示不可打印的字符）：

$ sed -r 'N;s/^([[:space:]]*hardware.*)(\n})$/\1\n\t\2/;t;P;D' infile | cat -A
lease 192.168.6.100 {$
  binding state free;$
  hardware ethernet 00:e0:4c:68:00:96;$
^I$
}$
lease 192.168.6.100 {$
  binding state active;$
  hardware ethernet 00:e0:4c:68:00:96;$
  client-hostname "andrew-H81M-S2PH";$
}$
lease 192.168.6.100 {$
  binding state free;$
  hardware ethernet 00:e0:4c:68:00:96;$
^I$
}$
lease 192.168.6.100 {$
  binding state active;$
  hardware ethernet 00:e0:4c:68:00:96;$
  client-hostname "andrew-H81M-S2PH";$
}$

这不是删除匹配，而是捕获应该围绕空行的两行，并替换之间的换行符和制表符。我还添加了一些锚点以便更安全地匹配。

涉及一些技巧，因为模式空间在替换后包含两个换行符，但P;D仅打印第一行并开始一个新的循环，这也导致在包含{{的行后面出现不需要的换行符1}}。

更详细地解释：

client-hostname

Answer 2

我冒昧地添加另一个卷曲......

../branches/my-branch

匹配两条线，替换为三条线

2 个答案: