Question

给出以下排序文件（myfile.txt）：

http://quarterly.mayo.edu/photoListing/default.cfm?summary=&displaymode=&reporting_unit_code=
http://quarterly.mayo.edu/photoListing/default.cfm?summary=&displaymode=&reporting_unit_code=
http://quarterly.mayo.edu/photoListing/default.cfm?summary=&displaymode=&reporting_unit_code=
http://quarterly.mayo.edu/photoListing/default.cfm?summary=&displaymode=&reporting_unit_code=
http://quarterly.mayo.edu/photoListing/default.cfm?summary=&displaymode=&reporting_unit_code=
http://quarterly.mayo.edu/photoListing/default.cfm?summary=&displaymode=&reporting_unit_code=
http://quarterly.mayo.edu/photoListing/default.cfm?summary=&displaymode=&reporting_unit_code=
http://quarterly.mayo.edu/photoListing/default.cfm?summary=&displaymode=&reporting_unit_code=
http://quarterly.mayo.edu/photoListing/default.cfm?summary=&displaymode=&reporting_unit_code=
http://quarterly.mayo.edu/photoListing/default.cfm?summary=&displaymode=&reporting_unit_code=
http://quarterly.mayo.edu/photoListing/default.cfm?summary=&displaymode=&reporting_unit_code=
http://quarterly.mayo.edu/photoListing/default.cfm?summary=&displaymode=&reporting_unit_code=
http://quarterly.mayo.edu/photoListing/default.cfm?summary=&displaymode=&reporting_unit_code=
http://quarterly.mayo.edu/photoListing/default.cfm?summary=&displaymode=&reporting_unit_code=
http://quarterly.mayo.edu/photoListing/default.cfm?summary=&displaymode=&reporting_unit_code=
http://quarterly.mayo.edu/photoListing/default.cfm?summary=&displaymode=&reporting_unit_code=
http://quarterly.mayo.edu/photoListing/default.cfm?summary=&displaymode=&reporting_unit_code=
http://quarterly.mayo.edu/photoListing/default.cfm?summary=&displaymode=&reporting_unit_code=
http://quarterly.mayo.edu/photoListing/default.cfm?summary=&displaymode=&reporting_unit_code=
http://quarterly.mayo.edu/photoListing/default.cfm?summary=&displaymode=&reporting_unit_code=
http://quarterly.mayo.edu/photoListing/default.cfm?summary=&displaymode=&reporting_unit_code=
http://quarterly.mayo.edu/photolisting/default.cfm?summary=&displaymode=&reporting_unit_code=

当我尝试：

uniq -c myfile.txt

我明白了：

21 http://quarterly.mayo.edu/photoListing/default.cfm?summary=&displaymode=&reporting_unit_code=
   1 http://quarterly.mayo.edu/photolisting/default.cfm?summary=&displaymode=&reporting_unit_code=

我猜这可能表示隐藏的角色或其他东西 - 但是当我尝试时：

uniq -u myfile.txt

我得到了预期的结果：

http://quarterly.mayo.edu/photolisting/default.cfm?summary=&displaymode=&reporting_unit_code=

这是一个真正的不一致，还是我错过了什么？谢谢，人

Answer 1

uniq -u仅打印唯一的行。您的myfile.txt显然有21条相同的行，后跟一条唯一行。 uniq -u仅打印一个唯一的行。

uniq myfile.txt应该打印两行，第一行对应21条相同的行，第二行对应最后的非匹配行。

例如：

$ ( echo foo ; echo foo ; echo bar ) | uniq -c
      2 foo
      1 bar
$ ( echo foo ; echo foo ; echo bar ) | uniq -u
bar
$

至于为什么uniq -c产生2行输出而不是1，它是因为你的最后一行与前面的21行不同。您在第22行上有photoListing（大写L），第22行有photolisting（小写l）。

（我的第一个想法是你可能在文件中有一些隐藏的字符;因为你在Cygwin上，不一致的行结尾是最可能的罪魁祸首。要查看隐藏的字符：

uniq -c myfile.txt | cat -A

但事实证明这不是问题。）

cygwin uniq无法正常工作

1 个答案: