Question

如何在shell脚本中获得以下结果？

This is line 1  
This is line 2  
This is line 3  
This is line 4  
This is line 5  
This is line 6  
This is line 7  
This is line 8  
This is line 9  
...  
...

期望的输出：

This is line 1 This is line 2 This is line 3  
This is line 4 This is line 5 This is line 6  
This is line 7 This is line 8 This is line 9  
... ... ....  
... ... ...

Answer 1

awk是你的朋友：

$ awk 'ORS=NR%3?FS:RS' file
This is line 1   This is line 2   This is line 3  
This is line 4   This is line 5   This is line 6  
This is line 7   This is line 8   This is line 9

与以下内容相同：

$ awk 'ORS=NR%3 ? " " : "\n"' file
This is line 1   This is line 2   This is line 3  
This is line 4   This is line 5   This is line 6  
This is line 7   This is line 8   This is line 9

解释

如果记录数不是3的倍数，则将输出记录分隔符设置为空格;否则，作为新行。

ORS定义输出记录分隔符。
NR定义记录数（本例中为行）。
FS定义字段分隔符。默认值为" "（空格）。
RS定义记录分隔符。默认值为"\n"（新行）。

Idiomatic awk中的更多信息和相关示例。

Answer 2

试试这个，

paste -d " " - - - < file

此空格作为分隔符的粘贴命令将3个连续的行组合成一行。

Answer 3

sed version

sed -e '$ b print
N
$ b print
N
:print
s/\n/ /g' YourFile

如果只有3行中的多行，则$ b print和:print不是必需的

在一个行版本

非GNU sed（就像我的AIX）

sed -e '$bprint' -e 'N;$bprint' -e 'N;:print' -e 's/\n/ /g' YourFile
对于GNU sed（没有经过测试，在这里缺少linux）

sed -e '$bprint;N;$bprint;N;:print;s/\n/ /g' YourFile

Answer 4

这可能适合你（GNU sed）：

sed '$!N;$!N;y/\n/ /' file

递归加入N行

4 个答案:

解释