假设我们有3个文件N1 N2 N3要比较。
将所有值添加到一个新的文件中，删除重复项。
然后将每个文件与主文件“out”进行比较，并为每次比较输出Missing。
然后将缺失的值添加到一个文件中，对它们进行排序并删除重复的值。

sort -u N1 N2 N3 > out
sort N1 | comm -2 -3 out > Missing1
sort N2 | comm -2 -3 out > Missing2
sort N3 | comm -2 -3 out > Missing3
sort -u Missing1 Missing2 Missing3 > Missing.txt

其实这不是一件容易的事。你可以试试这个它使用GNU awk。

gawk 'function report() { printf("File \"%s\" has different number of lines: %d\nIt should be %d\n", FILENAME, FNR, o); exit } NR == FNR { a[NR] = $0; ++o; next } FNR > o { report() } a[FNR] != $0 { printf("Line %d of file \"%s\" is different from line in file \"%s\": %s\nIt should be: %s\n", FNR, FILENAME, ARGV[1], $0, a[FNR]); exit } ENDFILE { if (ARGIND > 1 && FNR != o) report() }' file1 file2 file3

脚本版本：

#!/usr/bin/gawk -f
function report() {
    printf("File \"%s\" has different number of lines: %d\nIt should be %d\n",
        FILENAME, FNR, o)
    exit 1
}
NR == FNR { 
    a[NR] = $0
    ++o
    next
}
FNR > o {
    report()
}
a[FNR] != $0 {
    printf("Line %d of file \"%s\" is different from line in file \"%s\": %s\nIt should be: %s\n",
        FNR, FILENAME, ARGV[1], $0, a[FNR])
    exit 1
}
ENDFILE {
    if (ARGIND > 1 && FNR != o)
        report()
}

用途：

gawk -f script.awk file1 file2 file3 ...

如果你已经安装了vim，那么发出这个命令

vim -d file1 file2 file3 ...