awk - 使用 AWK 提取和区分列

Question

我需要从任意数量的文件中提取第一列，并为缺少的条目打印带有空行的列。空白行部分有问题。像这样：

File1:
Alfa        Something    More stuff
Charlie     Something    More stuff
Delta       Something    More stuff
Echo        Something    More stuff
Foxtrot     Something    More stuff

File2:
Alfa        Something    More stuff
Bravo       Something    More stuff
Echo        Something    More stuff
Foxtrot     Something    More stuff

File3:
Alfa        Something    More stuff
Bravo       Something    More stuff
Charlie     Something    More stuff
Delta       Something    More stuff
Echo        Something    More stuff

Output:
FileName1    FileName2    FileName3
=========    =========    =========
Alfa         Alfa         Alfa
             Bravo        Bravo
Charlie                   Charlie
Delta                     Delta
Echo         Echo         Echo
Foxtrot      Foxtrot

Answer 1

这是一种方法，除了一些小的格式问题：

awk '
  { 
    exists[$1] = 1;
    files[$1,ARGIND] = 1;
  }
  END {
    for (i=1; i<ARGC; ++i) {
      printf("%-20s",ARGV[i])
    }
    printf("\n");
    for (i=1; i<ARGC; ++i) {
      printf("%-20s","=================")
    }
    printf("\n");
    for (name in exists) {
      for (i=1; i<ARGC; ++i) {
        if (files[name,i]) {
          printf("%-20s",name);
        }
        else {
          printf("%-20s","");
        }
      }
      printf("\n");
    }
  }
' file1 file2 file3