Linux file-related commands

1.cd

(1) Function: Change the current path

(2) Format: cd[path] ex:cd/document/

(3) Description: CD./indicates the current path CD. /indicates Upper path

2.ls

(1) Role: Listing directory and file information

(2) Format: LS [option] [file] ex:ls-l indicates the details of all files in the current directory are listed

(3) Description: If you want to display. Start with a hidden file that can be used only with-a

3.cat

(1) Function: Connect and display information about one or more of the files specified

(2) Format: Cat [Options] file 1 file 2 ... ex:cat-n hello1.c hello2.c can output all the contents of files 1 and 2, including blank lines

(3) Description:-n is output to all rows starting with the first line-B and-n are similar, except that blank lines are not displayed

4.cp

(1) Role: Copy files to the specified directory

(2) Format: CP [option] The original file or directory destination file or directory ex:cp-a./Copy all files under the./my/why to the current directory

5.chmod

(1) Role: Change the access rights of the file

(2) Format: chmod [options] octal permissions file ex:chmod 777 *

(3) Description: Use chmod must have root authority

Format R-w-x (R for Read, W for write, X for execution)

Binary rwx	Octal	corresponding permissions	Binary rwx	Octal	corresponding permissions
000	0	Does not have any permissions	001	1	can only perform
010	2	Write only	011	3	Write-Only and executable
100	4	Read-only	101	5	Read-Only and executable
110	6	Readable and writable	111	7	Readable writable Executable

6 , modify Volume

First look at all the settings under the Alisa driver
amixer Contentsto modify the values commandAmixer Cset XXXX (the name to be set, Numid\iface\name) XX (the value to set)
7. View process Ps-aux 8, end a process kill XX (process number) 9, request IP address UDHCPC->enter

Linux file-related commands