bash - 在 BASH 中分两列输出一个文件

Question

我想在第 n 行之后将文件重新排列成两列。

例如，假设我这里有一个这样的文件:

This is a bunch
of text
that I'd like to print
as two
columns starting
at line number 7
and separated by four spaces.
Here are some
more lines so I can
demonstrate
what I'm talking about.

我想像这样打印出来:

This is a bunch           and separated by four spaces.
of text                   Here are some
that I'd like to print    more lines so I can
as two                    demonstrate
columns starting          what I'm talking about.
at line number 7

我如何使用 bash 命令或函数来做到这一点？

Answer 1

实际上，pr 几乎可以做到这一点:

pr --output-tabs=' 1' -2 -t tmp1 

↓

This is a bunch                     and separated by four spaces.
of text                             Here are some
that I'd like to print              more lines so I can
as two                              demonstrate
columns starting                    what I'm talking about.
at line number 7  

-2 两列； -t 省略页眉；如果没有 --output-tabs=' 1'，它会为它添加的每 8 个空格插入一个制表符。您还可以设置页面宽度和长度(如果您的实际文件长于 100 行)；查看 man pr 以获得一些选项。

如果您确定“比左边最长的一行多四个空格”，那么您可能需要使用更复杂的东西；

以下内容适用于您的测试输入，但已到达正确答案应该是“已经使用 Perl；”的地步；

#!/bin/sh
infile=${1:-tmp1}
longest=$(longest=0;
          head -n $(( $( wc -l $infile | cut -d ' ' -f 1 ) / 2 )) $infile | \
              while read line
              do
                  current="$( echo $line | wc -c | cut -d ' ' -f 1 )"
                  if [ $current -gt $longest ]
                  then
                      echo $current
                      longest=$current
                  fi
              done | tail -n 1 )
pr -t -2 -w$(( $longest * 2 + 6 )) --output-tabs=' 1' $infile

↓

This is a bunch           and separated by four spa
of text                   Here are some
that I'd like to print    more lines so I can
as two                    demonstrate
columns starting          what I'm talking about.
at line number 7          

... 重新阅读您的问题，我想知道您的意思是不是要从字面上指定程序的第 nth 行，在这种情况下，除非该行发生，否则以上都不会起作用半途而废。