About the format and usage of some Linux commands (Linux Employment Class second assignment)

Common basic Commands:

cd command: Change directory

CD [/path/to/somewhere]

Cd

CD ~: Back to home directory

CD ~username: Switch The home directory for the specified user

CD-: Go back to your previous directory

Related environment variables:

Pwd:

OLDPWD:

PWD command: Printing working directory

Show working directory

Ls:list

Lists the property information for a file or directory under a specified path

Metadata: Attribute Data

Data:

ls [OPTION] ... [FILE] ...

-L: Display with long format

Drwxr-xr-x 1 root root 8 08:47. cache

D: File type

Rwxr-xr-x: Permissions, Mode

1: Number of times a file has been hard linked

Root:owner, belonging to the Lord;

Root:group, genus Group

8:size, Default is byte

23 08:47 Modify Timestamp

. cache: File name

-D: Display the directory's own properties

-h:human-readable

-A: Displays all files, including. Start hidden files

.: Current Directory

..: Parent Directory

-r:reverse, Reverse display

-r:recusive, recursive

Text file view commands for the class:

Cat, TAC Command:

Cat [OPTION] ... [FILE] ...

-N:

-E:-ve

-E: Display line terminator

-V: Display nonprinting characters

File content Type view command:

File/path/to/somewhere

Echoing command: Echo

echo [OPTION] ... [ARGS] ...

-N: No line break;

-e: Allow the control to take effect;

\n:new Line

echo "$VAR _name"

Command path location View tool:

Whereis, which

Which:

which [options] [--] programname [...]

--skip-alias: Prohibit listing aliases

Whereis COMMAND:

Displays the path to the binaries, source files, and help manuals;

Time-related commands:

Rtc:realtime Clock

System clock: Systems clocks

Date: System time

Clock, Hwclock: Hardware time

Date

Date [OPTION] ... [+format]: Time display

FORMAT

%F

%d

%T

%H

%M

%s

Date [MMDDHHMM[[CC]YY][.SS]]: Time setting

Hwclock

-s:hctosys, with hardware clock as the standard, adjust the system time with the hardware;

-W:SYSTOHC, whichever is the system clock

Cal:

Cal [year]

Shutdown or restart

shutdown: Halt, Poweroff, Init 0, shutdown-h time

restart: reboot, init 6, Shutdown-r time

shutdown

shutdown [OPTIONS ...] [TIME] [WALL ...]

-R: Restart

-H: Shutdown

--no-wall

-C

Time:

+m: The corresponding operation is performed after the relative length, and the unit is minutes;

hh:mm Absolute Time

Stat

W, who, WhoAmI

About the format and usage of some Linux commands (Linux Employment Class second assignment)