[Linux nurturance Program] About Linux

One, the difference between Linux and window

1. Linux is strictly case-sensitive

2. Everything in Linux exists in the form of a file

3. Linux does not rely on the suffix name as the file type, but has a conventional suffix name

. gz. bz2. tar.bz2. tgz compression Pack

. html. PHP Web page

. RPM Binary Packages

. sh Script File

. conf configuration file

4. Window programs cannot be installed and run directly on Linux systems.

Second, the command format (ctrl+l clear screen)

1. [Email protected] ~]#

Root current user, root is super Administrator

localhost Host name IP

~ Current Directory

# Super Admin logon prompt $ Normal user logon prompt

2. View the commands for the files in the directory

ls [options] [Parameters: File or directory]

Option:-A to show all files including hidden files

-L Show more information

-D Displays the directory properties instead of displaying all the files in the directory

-H humanized Display file size

-I display Inode

File permission plus type: represented by a 10-bit symbol

The first bit is file type:-file D directory L link

The latter nine bits are divided into three groups, each representing

3. Directory Processing commands

Show current directory pwd

New catalog Mkdir-p [params]

-P recursive creation of multilevel directories

Go to Catalog CD ~ Show back to home directory

CD does not pass parameters to the home directory

Cd.

Cd..

CD-Go back to the previous catalog

Delete directory rmdir can only delete empty directory

So it's usually used RM-RF [path]

-R Delete

-F Mandatory Force

Copy a directory cp-a the file or directory to be copied the newly copied file name or directory name

-R

-A

Cut or rename directory and file mv This command has no parameters

4. File processing commands

A. File Search command Locate

can only search file name, database location/var/lib/mlocate

Database updates once a day, forcing updates to use UpdateDB

Database configuration file/etc/updatedb.conf

B. Command search command which Whereis

View command location options have-m-b

-B Find only executable files

-M find only help documents

C. Echo $PATH

Display System Environment variables

D. File Search command find

Find search Location Options parameter

The search location can be an absolute path, or it can be the current path (.). Use a dot to represent

find/users-name [file] Search file name [file] can use *? [] Match

find/users-iname [file] iname means ignoring case

find/users-root [user] to find files with the file owner as [user]

Find/users-nouser find files with no owner

Find/users-atime +10 files that find file access time 10 days ago

Find/users-ctime 10 Find modified file properties date 10 days ago File

Find/users-mtime-10 Find files that modify the contents of a file within 10 days

Find. -size [Size] Search file size is equal to size of file, size can also contain symbol + representation greater than-indicates less than

Find. -inum [num] Search file i node equals num

Search criteria can use logical commands such as-a-o

-A represents the logic and

-O represents a logical OR

The results found can be used to execute subsequent commands.

-exec [command] {} \; Note {} \; This four character is a required format

Find. -size +20k-a-size-50k-exec Ls-lhi {} \;

E. grep command for searching strings

Searches for a string in the specified file that satisfies the matching criteria

grep option String file name

Grep-i-v [str] [file]

5. Help commands

The function is to view the Help document for the command

Syntax is man [command]

Mans LS

man-f [command] to see which level of a command has a help document equivalent to Whatis

man [level] [command] to view the command's appropriate levels of help document

man-k [command] to find all commands related to the specified command

Shell internal commands use help [command]

[Command]--help

info [command]

6. Compress file Commands

File compression format. zip. gz. bz2. tar.gz. tar.bz2 Five common formats

A. zip compression format

Zip destination filename Original file name

Zip-r target directory name original directory name

Unzip original file name

Unzip original directory name

B. GZ compression format

Gzip

Gzip-d

Gunzip

7. Restart and shutdown commands

Shutdown-r [TIME] &

Shutdown-h [TIME]

Shutdown-c

RunLevel

init [level]

Configuration file/etc/inittab

Logout

[Linux nurturance Program] About Linux