Linux basic commands, and get command help information

Order format: command [OPTIONS ...] [ARGUMENTS ...]

COMMAND:

Initiating a command: Requests that the kernel run a binary program as a process;

Programs--Process

Static--Dynamic (with life cycle)

Examples take centos6.5 as an example.

1. Ifconfig: View all network card information

2. Echo: Echoing

-N: No line break;

-E: Let the transfer character take effect;

\ n: Line break

\ t: Tab

3. TTY: View terminal equipment

4. STARTX: Start x Windows

5. Export: setting or displaying environment variables

• -F represents the function name in [variable name].

• -n Deletes the specified variable. The variable is not actually deleted, but is not exported to the execution environment of the subsequent instruction

• -p lists all the environment variables that the shell assigns to the program

6. PWD: Show Current working directory

7. History: Used to display a specified number of command commands, read directories in the history file to the historical buffer directory to write to the command file

-C: Clears the current History command

-A: Writes the command in the history command buffer to the history command file???

-r: Reads commands from the history command file into the current history command buffer

-W: Writes the current History command buffer command to the history command file

-N: Print last N history command

8, Shutdown: Shutdown command

-H: System shutdown

-R: Rebooting the System

-K: Send shutdown information to all current users

-C: Cancel shutdown

9, Poweroff: Shut down the computer operating system and cut off the system power

-D: Do not write the operation to the log file when shutting down the operating system

-F: Force reboot, do not invoke shutdown command function

10. Reboot: Used to restart the operating system in progress

-D: Do not write data to data file when rebooting

-F: Force reboot, do not invoke the function of shutdown instruction

11. Hwclock: Display or This is a hardware clock

-r,–show reading the hardware clock and printing the results

–set set RTC to –date specified time

-s,–hctosys Setting the system time from the hardware clock

-W,–SYSTOHC setting the hardware clock from the current system time

12. Data: Display or set the system time and date

-d< "string";: Displays the date and time that the string refers to

-s< "string";: Set date and time

Help for getting commands on a Linux system

1. Internal command:

Help COMMAND

2. External command:

2.1, command to bring the use of a brief format to help

# COMMAND--help

2.2. User manual: Manual

Location:/usr/share/man

# Man COMMAND

3.3, User manual: Compressed format of the file, a section of the

/usr/share/man

Man1, Man2, ...

1: User command;

2: System call;

3:c Library call;

4: Equipment files and special documents;

5: File format; (configuration file format)

6: Game use help;

7: Miscellaneous;

8: Management tools and guardian;

Linux basic commands, and get command help information