Sed 命令在没有给定的位置时,默认会处理所有行; Sed 支持一下几种地址类型:1、 first~step 这两个单词的意思: first 指起始匹配行, step 指步长,例如: sed-n 2~5p 含义:从第二行开始匹配,隔 5 行匹配一次,即 2,7,12...。2、 $ 这个$符表示匹配最后一行。3、 /REGEXP/这个是表示匹配正则那一行,...
-o (--only-matching)只输出匹配的选项(不显示整行) -w 完全匹配字词(精确匹配) -x 仅完全匹配一行 -c (--count)只打印每个文件匹配的行数 -v (--invert-match)取反,打印不匹配的行 -V 显示版本信息 --color 将匹配到的内容进行着色 --help 显示帮助 -B NUM (--before-context=NUM) 显示匹配到的...
第1域是帐号名,第5域是帐号所有者。 $ pg passwd.awk #!/bin/awk -f # to call: passwd.awk /etc/passwd # print out the first and fifth fields BEGIN{ FS=":"} {print $1,"\t",$5} $ passwd.awk /etc/passwd root Special Admin login xdm Restart xdm Login sysadm Regular Admin login...
作为一名合格的程序员，在实际开发中，我们不免会连接服务器终端执行一些运维操作，在服务器上那必然是没...
这时候可以用sed 的n 命令和 b命令: “n” 命令表示：将当前行的下一行读入到pattern space, 从而...
I am trying to create a regexp that matches the first line, but not the second. For example I try this: user@lab-client:~$ cat tabmatch.input |awk '/\t: \(test/ { {print $2} }' (test1 (test2 Even though specify only one \t and then ":", it still matches on two \t an...
java中Array（数组）的用法
The sub function replaces only the first match whereas gsub function replaces all the matching occurrences. By default, these functions operate on $0 when the input string isn't provided. Both sub and gsub modifies the input source on successful substitution. $ # for each input line, change ...
Is there a method in awk for splitting only the first N columns? If you know N a priori, you might prepare regular expression and use it in sub String Function, in that particular, let file.txt content be 1.1 1.2 data for row1 2.1 2.2 data for row2 ? ? data for row3 \ * data...
Please note that sub replacesonly the 1st occurrence of the match. $catsub.awkBEGIN { state="CA is California"sub("C[Aa]","KA",state); print state; } $awk-f sub.awkKA is California The 3rd parameter string-variable is optional. When it is not specified, awk will use $0 (the cu...