Linux uniq命令

uniq常见参数

在每行前加上目前出现次数的编号
-c, --count prefix lines by the number of occurrences

仅仅输出重复的行
-d, --repeated only print duplicate lines, one for each group

输出所有重复的行
-D, --all-repeated[=METHOD] print all duplicate lines
groups can be delimited with an empty line
METHOD={none(default),prepend,separate}

比较时跳过前N列
-f, --skip-fields=N avoid comparing the first N fields
–group[=METHOD] show all items, separating groups with an empty line
METHOD={separate(default),prepend,append,both}

比较时，忽略大小写
-i, --ignore-case ignore differences in case when comparing
比较时跳过前N 个字符
-s, --skip-chars=N avoid comparing the first N characters

去除重复的行
-u, --unique only print unique lines

使用’\0’作为行结束符，而不是新换行
-z, --zero-terminated end lines with 0 byte, not newline

对每行第N 个字符以后的内容不作对照
-w, --check-chars=N compare no more than N characters in lines

帮助
–help display this help and exit

版本
–version output version information and exit

例子

[root@hdfa67 txt]# cat word
the day is sunny the the
the sunny is is

[root@hdfa67 txt]# cat word |xargs -n 1
the
day
is
sunny
the
the
the
sunny
is
is

• -c

[root@hdfa67 txt]# cat word |xargs -n 1 | sort | uniq -c
      1 day
      3 is
      2 sunny
      4 the
[root@hdfa67 txt]# cat word |xargs -n 1 | uniq -c
      1 the
      1 day
      1 is
      1 sunny
      3 the
      1 sunny
      2 is

• -d

[root@hdfa67 txt]# cat word |xargs -n 1 | uniq -d
the
is

• -D

[root@hdfa67 txt]# cat word |xargs -n 1 | uniq -D
the
the
the
is
is

• -u

[root@hdfa67 txt]# cat word |xargs -n 1 
the
day
is
sunny
sunny