Zy-2015-08-27

Summarize the methods and examples of the commands involved in this course, summarize basic regular expressions and extended regular expressions to display lines ending in bash in the/etc/passwd file

Egrep ' bash$ '/etc/passwd

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Displays the two-digit or three-digit number in the/etc/passwd file

Egrep ' \<[[:d igit:]]{2,3}\> '/etc/passwd

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Show netstat -tanLine ending with ' LISTEN ' followed by 0, one, or more whitespace characters in the command result

Netstat-nat | Egrep ' \<listen[[:blank:]]* '

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Add user bash, Testbash, basher, and Nologin user (Nologin the user's shell is/sbin/nologin), and then find the row in the/etc/passwd file that has the same user name as its shell name

Egrep ' ^ ([[:alnum:]]*\>). *\1$ '/etc/passwd

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Displays the default shell and UID for root, CentOS, or User1 users on the current system (please create these users beforehand, if not present)

Egrep ' ^ (centos|user1|root) '/etc/passwd | Cut-d:-f3,7

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Find a word in the/etc/rc.d/init.d/functions file (the middle of the word can be underlined) followed by a set of parentheses on the line

Egrep ' ([[: Alpha:]]|_) +\ (\) '/etc/rc.d/init.d/functions

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Use echo to output a path, then egrep to find its path base name, and further use Egrep to remove its directory name

1. Egrep . ..//todo

Find the number between 1-255 in the ifconfig command execution result

Ifconfig | Egrep ' \< (1?[ 1-9]{1,2}|2[0-5]{2}) \> '

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This article is from the "Robot" blog, make sure to keep this source http://molloc.blog.51cto.com/1143037/1689701

Zy-2015-08-27