Linux Common Commands (second Edition)--File Search command

File Search Command

1,which/usr/bin/which# display system command directory , Absolute Directory, can not find files

Format: which [ system command ]

E.g.which ls

Attached-whereis: can also find the absolute path of the command

Unlike Whereis , which lists the alias record for this command , and whereis displays the location of the Help document for the command.

2,find/usr/bin/find# file or directory, any file can, tablets, compressed package, etc.

Syntax:find [ search Path ] [ search Options ] filename

A)find/etc-name file name #-name most common options

Find/etc-name init// Find the file init file in the directory / etc

Attention:

As far as possible to narrow the scope of the search, do not look in the root directory, otherwise: 1, the search is very slow, 2, occupy a large number of system resources .

2- consume less system resources better , and try to find with find when the server is under a low pressure .

3-find. -name search results are different from Windows , such as: Windows will list all The files that contain the INIT keyword and Linux it will only match Init Key Words

4- Use a wildcard character :

*: Used to match any character

Find/etc-name init* #查找所有以 files that begin with Init

Find/etc-name *init* #init There are no spaces around to find all files that contain the init keyword

?: Used to match a single character

Find/etc-name Init??? #这个文件会有七个字符.

Find/etc-name init??

b)find/etc-size File Size

#他是以数据块为单位的! + byte = 0.5KB, 1K = 2Blocks

100m=? Blocks

100M = 102400K = 102400*2blocks

e.g

Find/etc-size +204800 #在/ etc to find files larger than 80MB greater than 100MB

find/etc-size-204800# in /etc to find files larger than 80MB less than 100MB

Find/etc-size 204800# in/ etc look for files equal to 100MB , not used!

C)find/etc-user username find files belonging to username

Find/home/xiaofang/programme/data_structure/-user Xiaofang

D) Find by Time value:

1. In days:ctime,atime,mtime

2, in minutes:cmin,Amin,mmin#更为常用

C-change change: indicates that the properties of the file have been modified , such as: Owner, owning group, permission

A-access Access: File has been browsed

M-modify Modification: The contents of the file have been modified

-How long,+ how much time

e.g.

Find/etc-mtime-1

Find/etc-amin-60

find/home-cmin-120

e)find/etc-type file Type # find by file type

F Binary Files

L Soft Link File

Catalog D

e.g.

Find/etc-type F

Find/etc-type L

F)-inum# Search based on I node

e.g.

Touch---abc# Delete : RM---ABC

Touch "A B" # delete : RM "a B"

Find. -inum 159341

Find. -inum 159341-exec rm-f {} \; #找到i - node 159341 file, and delete it

Attached-find connector:

1,-a: and Logic and

-O: or logical OR

e.g.

Find/etc-size +163840-a-size 204800# find >80m,<100m files

Find/etc-name init*-a-type F # finds files named init and is binary and does not contain directories

2.find ...-exec command {} \; #固定格式, that's the only way to write.

{}:find Query results

\: escape character -makes the symbolic command use its own meaning

;: Statement End

e.g.

Find/etc-name inittab-exec ls-l {} \;

Find the inittab file under #在/ etc and display its details

Find/home-user sax-exec rm-rf {} \;

#删除用户 all of sax files

Find/home-user sax-ok rm-rf {} \;#-ok connector

#删除用户sax All the files , he will prompt you whether to confirm

Find/etc-name init*-ok rm-rf {} \;

3. locate[list file in Databases]:/usr/bin/locate

Description

#是Linux -specific commands to find files or directories, preferably for quick location system Commands , configuration files , etc.

# Although the search is fast, but sometimes it can't be found

#locate is found in the file database, so the speed will be fast

# But if the database does not contain this file, he will not find it;

Format: Locate [ search keywords ]

Mates: updatedb [Update a database for Mlocate]:/usr/bin/updatedb

#建立整个系统目录文件的数据库

Note: Its execution permissions are:root!!!

4.grep:/bin/grep# searches the file for string matching lines and outputs

Format: grep [ Specify String ] [ source file ]

E.g.grep ftp/etc/services

Attached:grep is particularly powerful, supports regular expressions, and her more specific introduction please refer to my other blog post:

Four days proficient in shell programming ( two )

Linux Common Commands (second Edition)--File Search command