date: (- set, set) the date and time display function
lscpu: cpu will print the details of the information terminal
free-h: print memory, -h option means to convert the result to a more appropriate display unit
sudo: carrying administrator privileges command back then, the command is executed, because under normal circumstances is not the default administrator (root) privileges
sudo fdisk -l: fdisk displays disk information, so the information listed option -l represent disk
lsusb: find so USB peripherals
uname: (- m, cpu type output), the information system of the printing operation, -a after adding parameters, print information about the details of the operating system
ifconfig: print out the details of the information ip address, on behalf of etho Ethernet interfaces, wlan0 representatives wifi interfaces, lo is out of the virtual local interface
2. Raspberry pie dedicated query
vcgencmd: View hardware status
parameter:
measure_temp: measure_temp is a command parameter, this parameter returns the actual temperature of the cpu
measure_volts core: the core voltage detection
View BCM2835 Soc temperature
vcgencmd measure_temp
codec_enabled CODEC: Check whether the decoder is turned on
codec_enabled codec: Check whether the decoder is turned on
A shell is what?
Unix shell is interactive pages of text, as long as the command name with the system operation can be carried out
which: it can be carried out to determine whether an executable file by this command
alias: a command to another name, alias freak = "freak -h", meaning that when the input freak, equivalent to freak-h
type: understand the type of command
Learn how a new command:
whatis: a very brief statement statement to describe this command
man: print out the details of the command information
info: More details of the return information
nano editor operations:
Followed immediately file name, if the current directory exists open, or create
hot key:
crtl + O-- save, crtl - X is the exit
The representative of the ctrl key, M for alt, on behalf pressing Ctrl and G ^ g
Tips:
M- \: Move the cursor to the beginning of the text
M- /: Move the cursor to the end of the text
^ K: Cut selected text
M-6: Copy the selected content
^ U: Paste
^ G: Help
After nano save the file will be generated in the current directory
cp: copy files, copy the file name of the new file name
rm: deleting files
mv: certain file location, if not the absolute position is equivalent to rename
pwd: output current path, in the same directory, there can not file with the same name, but you can change the directory to create the same file name
Raspberry Pi configuration;
Password: sudo passwd pi
Setting wifi connection:
Need to modify the configuration file
Nano the sudo / etc / wpa_supplicant / the wpa_supplicant.conf Network = { SSID = " WIFI_NAME " PSK = " wifi_password " } to add a plurality of wireless network configurations may be used to distinguish between two custom id_str WiFi Network = { SSID = " wifi_name1 " PSK = " wifi_password1 " ID_STR = " Class1 " } Network = { SSID = " wifi_name2 " PSK = " wifi_password2 " ID_STR = " Class2 " } If you have a range of two networks, can be added to the priority option to choose between them. The range of the network with the highest priority will be the network connection. Network = { SSID = " wifi_name1 " PSK = " wifi_password1 " priority =. 1 ID_STR = " Class1 " } Network = { SSID = " wifi_name2 " PSK = " priority = 2 ID_STR = " Class2 " } Add WIFI network without a password added to no WIFI network passwords just key_mgmt set to NONE Network = { SSID = " WIFI_NAME " key_mgmt = NONE } to see if the wifi connection successfully after the configuration We need to restart raspberry Pi, in order to see whether the configuration. ifconfig wlan0
Shutdown
sudo
shutdown
-h now
sudo
halt
sudo
poweroff
sudo
init 0
Restart
sudo
reboot
shutdown
-r now
shutdown
-r 18:23:52
#定时重启在18点23分52秒关闭
Software upgrades and installation
sudo apt-get update: Get the latest software list
sudo apt-get upgrade upgrade the installed files
sudo apt-get install mysql: mysql installation
Software uninstall and delete
sudo apt-get remove mysql: delete the software, configuration files are not deleted
sudo apt-get purge mysql: uninstall software, delete profiles
ssh connection
May be connected by the ip address of the router xshell
Raspberry Pi can be queried by ifconfig ip address
File transfer:
If it is Linux or macOS system, you can transfer files via sftp command
sftp [email protected], the password may be connected
$ Ls: view files on the local computer
$ Lls: view files on a remote computer
$$ pwd: View the current path of Raspberry Pi
$$ lcd: go back one level
$$ get remote.file: come in to download files from raspberries
GPIO
Knowledge in this regard does not yet have replenished
Daemon:
Into the configuration file etc / motion / motion.conf
The need to guard the process is set to yes
file:
The file system can be seen as a tree, the tree node is a directory of files, subdirectories pi become home, and home is the parent directory of pi, the absolute path to understanding the principle,
Read the home directory to find the file directory location of the file, how to read pi from home, then layer by layer to find, ultimately directory you want files to be read
File Operations
touch file: create a file by touch
mkdir: create a new directory
rmdir: delete a directory
cp: cp command to supplement the above, after the addition -r parameter can copy a whole directory tree
File Search: You can traverse the file system by the find command
find / -name "* .c" will be printed as a suffix .c files on the hard disk
locate: find command with the same, but the shrewd
locate the file: Find files -i ignore case, l * t, l have been the beginning of a file ending in t
clear: Clear Screen
ps: you can list the programs that are running