Linux Find using Tutorials

Find Basics

File Lookup: The process of locating a qualifying file on a file system;

File Lookup command: Locate, find

Locate: A non-real-time lookup tool that relies on a pre-built index, which is built automatically when the system is idle (periodic tasks), manually updating this database (updatedb), searching fast, and fuzzy lookups;

Find: real-time search; search speed slightly slow; exact search;

Find command:

Find [OPTION] ... [Find Path] [Search Criteria] [Handling Action]

Find path: Default to the current path;

Search criteria: The specified search criteria, can be based on the file name, size, genus of the main group, type, etc., by default to find all the files under the specified path;

Handling actions: What to do with the eligible files; By default, output to the screen;

Search criteria:

To find by file name:

-name "file name": Supports the use of glob (*,?, []);

-iname "file name": Character case insensitive, support for using Glob

-regex "pattern": matches the entire file path string with pattern, not just the file name

According to the genus, the genus Group looks for:

-user USERNAME: Find files that belong to the specified user

-group GROUPNAME:

-uid UserID: A file that finds the owner-specified UID of a file;

-gid GroupID:

-nouser: Find files that are not owned by the master;

-nogroup: Find files without a group;

To find by file type:

-type type

Type types are:

F: Normal file

D: Catalogue

L: Symbolic Link

B: Block device

C: Character device

P: Named Pipes

S: Socket

Combination Lookup criteria:

and Conditions:-A

or condition:-O

Non-conditional:-not,!

Depending on the file size, look for:

-size [+|-]num

Unit: K, M, G

+num: (Num,+oo] The value of the lookup if set to X (same as), the range is: X>=num

Num: (NUM-1, num] range is: num-1<=x<num

-NUM:[0,NUM-1] Range is: 0<x<num-1

Based on time stamp:

In "Days" as the unit

-atime (last accessed time)

+num:[num+1, +00] Range: x>num+1

num:[num,num+1) Range of num<x<=num+1

-num:[0,num) Range of 0<x<=num

Note: This must be distinguished from the-size value range, which is easily confused.

-mtime (last file modification time)

-ctime (last File property modification time)

Based on permissions:

-perm [/|-]mode

MODE: Exact permission match

/mode: Any one of a class of objects (U,g,o) is eligible for any of the rights, implied or conditional;

-mode: Every permission specified for each class of object must be in accordance with the condition;

Handling actions:

-print: Default handling action

-ls: Similar to the "ls-l" operation for each file found;

-delete: Delete the found file;

-fls/path/to/somefile: The detailed path information of the found file is saved to the specified file;

-ok COMMAND {} \;

The user must be confirmed beforehand before executing the specified command for each file;

-exec COMMAND {} \;

No user confirmation required;

Actual combat

1, find the/var directory is the owner of the root, and belong to the group mail all files;

Answer: find/var-user root-a-group Mail

2. Find all files that are not root, bin or hadoop under the/usr directory;

Answer: find/usr-not \ (-user root-o-user bin-o-user hadoop \)

3. Find all files whose contents have been modified and are not root or Hadoop for the last week in/etc directory;

Answer: find/etc-mtime-7-a-not \ (-user root-o-user hadoop \)

4. Find all files on the current system that are not owned by the master or group, and have been visited in the last week;

Answer: Find/\ (-nouser-o-nogroup \)-a-atime-7

5. Find all files in/etc directory greater than 20k and type ordinary files;

Answer: find/etc-size +20k-a-type F

6, look for all the users in/etc directory do not have permission to write files;

Answer: find/etc-not-perm/222

7. Find at least one class of users who do not have permission to execute files in/etc directory;

Answer: find/etc-not-perm-111

8, find/etc/init.d directory, all users have execute permission, and other users have write permission files;

Answer:find/etc/init.d-perm-111-a-perm-002

This article is from the "Wind Rhyme" blog, please be sure to keep this source http://chinalx1.blog.51cto.com/2334265/1691658

Linux Find using Tutorials