首页 > 其他 > 详细

awk引用外部变量问题

时间:2015-08-12 14:55:12      阅读:201      评论:0      收藏:0      [点我收藏+]
在awk中引用外部变量会无法生效,但使用双引号时候,内置变量会不识别;解决方法是使用三引号;

localhost ~]$ more awkfile
this is one
this is two
this is three
this is four
this is five
this is six
this is seven

$ awk ‘{print $3}‘ awkfile                             $ awk "{print $3}" awkfile   
one                                                            this is one                  
two                                                            this is two                  
three                                                          this is three                
four                                                            this is four                 
five                                                             this is five                 
six                                                               this is six                  
seven                                                          this is seven


[@localhost ~]$ more awk.sh
#!/bin/bash
echo "-----1111111111------------"
awk ‘NR==2 {print $3}‘ awkfile
echo "-----222222222-------------"
awk "NR==2 {print $3}" awkfile
echo "-----333333333-------------"
i=2
awk ‘NR==$i {print $3}‘ awkfile
echo "-----444444444-------------"
awk "NR==$i {print $3}" awkfile
echo "-----555555555-------------"
awk "NR==$i "‘{print $3}‘"" awkfile
[@localhost ~]$
[@localhost ~]$ sh awk.sh
-----1111111111------------
two
-----222222222-------------
this is two
-----333333333-------------
-----444444444-------------
this is two
-----555555555-------------
two
[@localhost ~]$


以上是个人浅薄经验,以此进行记录。

本文出自 “大亮” 博客,请务必保留此出处http://allveny.blog.51cto.com/8994099/1683930

awk引用外部变量问题

原文:http://allveny.blog.51cto.com/8994099/1683930

(0)
(0)
   
举报
评论 一句话评论(0
关于我们 - 联系我们 - 留言反馈 - 联系我们:wmxa8@hotmail.com
© 2014 bubuko.com 版权所有
打开技术之扣,分享程序人生!