Use the find command

find

effect ： It is often used to find files in the system

grammar ：

find  Lookup location   Find type   [ What to do after finding ]

Lookup location ： Absolute path or relative path
Find type ：

-name: Find... By filename 
-iname: Find in a case insensitive manner , Only support *?[]^ And so on 
-perm: Precise authority search , The mask value of the following permission , The usage of mask value is as follows ：
 	  755： lookup 777 Permission file 
 	  /222: Look for files where at least one type of user has write permission 
 	  /002: Find files that other users have write permission to 
 	  -222: Find files that all three types of users have write permission 
-user: Find... By user name 
-group: Find... By group name 
-nogroup: Find files that do not belong to a group 
-nouser: Find files that do not belong to the owner 
-regex: Match regular expressions to find ,
-iregex: Match regular and ignore case 
-type: Find by file type 
 	  f: Ordinary documents  d: Directory file  b: Block device file  c: Character device file 
 	  l: Link to the file  s: Socket character file  p: Pipeline files 
-size: Find by file size , contain K、M、G Company , A positive number means greater than , A negative number means less than , An integer is equal to 
-atime: Find by access days , Positive and negative integers are the same as above 
-mtime: Find by data modification days , Positive and negative integers are the same as above 
-amin: Find... In minutes of access , Positive and negative integers are the same as above 
-mmin: Find by data modification minutes , Positive and negative integers are the same as above 
-empty: Find empty file 
-follow: Such as find Command encountered symbolic link file , Trace to the file pointed to by the link 
-maxdepth: Start from the specified directory and look down several levels of directories 
-newer: Find all files that were modified before this file was modified 

Handling actions ：

-print: Output to the screen , No need to add , Default output to screen 
-ls: With ls Long file format output 
-delete: Delete the found file 
-fls  File path : Search the found file with ls The format of detailed information is output to a file 
-exec:  command  {
    } \; : Pass the found file to shell Command to process , With this command (|xargs shell command ) Achieve the same purpose 
	

Multiple lookup type connections ：

-a： Between two lookup types , Represents and 
-o： Between two lookup types , Represents or 
!: Before finding the type , Express non , Contrary to the search criteria 

example ：
1. Find with the ending file name

find /etc/ -name "*.conf"

2. File name ending with ( Ignore case ) Search for

find /etc/ -iname "*.conf"

3. Search by two names , Just match one of the names

find /etc/ -name "*.conf" -o -name "*.txt"

4. Search with regular expressions

find . -regex ".*\(\.txt|\.pdf\)$"

5. Negative condition lookup

find /etc/ ! -name "*.conf"

6. Search by file type , Find all the files in the directory

find /boot/ -type f

7. Find the files from the current directory of the bureau to the two-level directory of the deep level

find /etc/ -maxdepth 2 -type f

8. lookup 7 Files accessed within days

find /etc/type f -atime -7

9. lookup 7 Files accessed the day before yesterday

find /etc/ type -f -atime 7

10. lookup 7 Files accessed at all times before

find /etc/ -type f -atime +7

11. Find all files modified before modifying this file

find /etc/ -type f -newer /etc/fstab

12. Search by file size ,+5k Represents greater than 5k、-5k Represents less than 5k、5k Is equal to 5k

find /etc/ -type f -size +5k

13. Find an empty file and delete it , Three ways ：

find /etc/ -empty -delete
find /etc/ -empty -exec rm -rf {
    } \;
find /etc/ -empty |xargs rm -rf 

14. Find files according to file permissions

find /etc/ -type f -perm 777

15. Find out that the suffix in the directory is php, And permissions are not 755 The file of

find /etc/ -type f -a -name "*.php" -a ! -perm 755

16. Find the log files in the directory , And its existence exceeds 30 God , Copy it to /tmp Under the table of contents

find /var/log/ -name "*.log" -a -mtime +30 -exec cp -rf {
    } /tmp \;