仅当第二字段与字符串匹配时，如何获取文件的第一字段? [英] How to get 1st field of a file only when 2nd field matches a string?

问题描述

仅当第二字段与给定字符串匹配时，如何获取文件的第一字段?

How to get 1st field of a file only when 2nd field matches a given string?

#cat temp.txt

#cat temp.txt

Ankit   pass
amit    pass
aman    fail
abhay   pass
asha    fail
ashu    fail

---

cat temp.txt | awk -F"\t" '$2 == "fail" { print $1 }'*

无输出

推荐答案

当我最后删除 * 时，您的代码似乎可以正常工作

Your code seems to work fine when I remove the * at the end

cat temp.txt | awk -F"\t" '$2 == "fail" { print $1 }'

要检查的另一件事是文件是否使用制表符或空格.我的数据文件复制/粘贴复制了空格，因此我需要这一行:

The other thing to check is if your file is using tab or spaces. My copy/paste of your data file copied spaces, so I needed this line:

cat temp.txt | awk '$2 == "fail" { print $1 }'

另一种方法是使用grep:

The other way of doing this is with grep:

cat temp.txt | grep fail$ | awk '{ print $1 }'

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