Linux basic commands (partial)

Help: Assistance commands
Use format:
Help plus the commands you need to see, such as help PWD
Will get a description of the relevant command
Command--help, such as LS--help
will see the use of related commands

Man: Help manual command
Man plus commands to look at, such as man file
Get the user manual for the file command

Export the Help manual to a text file for learning
Man Plus Command | Col-b > Export File name
For example, the use of the LS command to export to a T60.TXT file
Man ls | Col-b > T60.txt
The meaning of Col-b is to remove special characters.

PWD: View your current directory

CD: Switch directories
For example, enter the T60 directory: CD T60
Switch to Parent directory: CD.
Switch to directory: CD/
Switch to the host directory: CD ~
Return to previous directory: CD-

ls: Show directory contents
Parameters:
-L: Display directory contents in a detailed list
-A: Show hidden files
-D: Show only the current directory's own properties
-H: Displays the file size in KB and needs to be used with-l
-r: Displays the contents of all subdirectories in the directory
For example, view the size of files and folders in the current directory: LS-LH
View the size of the T60 file under the root folder: Ls-lh/root/t60
View procedure supports wildcard characters,? Represents a character that represents any character
For example, look at all files in the root folder that begin with S: ls-lh/root/s. *

Du: Viewing the space consumption of directories and files
Parameters:
-A: All files are counted
-H: Display size in KB
-S: Total size of this directory
For example, view the total size of the root folder: Du-sh/root

mkdir: command to create a directory
Parameters:
-P: Creating nested Multi-level catalogs using
For example, create a/ROOT/T60/NB directory: Mkdir-p/ROOT/T60/NB

LN: Creating a Connection File
Parameters
-S: Create a soft link file
For example, linking/etc/httpd/conf/httpd.conf to/root/t60.conf
Soft: Ln-s/etc/httpd/conf/httpd.conf/root/t60.conf
Hard: ln/etc/httpd/conf/httpd.conf/root/t60.conf

CP: Copy command
Parameters:
-F: Overwrite file does not alert
-I: Overwrite file reminders
-P: Preserve file permissions before copying
-R: Add-r when copying directories
For example, copy the/etc/httpd/conf/httpd.conf file to/root/t71.conf
Cp/etc/httpd/conf/httpd.conf/root/t71.conf
For example, copy the/etc/httpd/conf/folder to/root/
Cp-r/etc/httpd/conf//root/

RM: Delete files or folders
Parameters:
-F: Direct Delete no reminders
-I: Reminders when deleting
-r: Delete entire directory tree
For example, delete the/root/conf/directory
rm-rf/root/conf/

MV: Moving files or directories
Effects similar to CP are used to rename files
For example, change T60 to S2t60
Mv/root/t60/root/s2t60

Which: Find the location of your Linux command file
For example, see where ls command file is
which LS

Find: Finding a file or directory
Parameters
-name: Search by file name, support wildcard characters?
-size: Search by file size, + number for file greater than XXK,-number is less than xxk file
-user: Search by file Owner
-type: Search by file type, F normal file, D directory, b device file (hard disk), C character device file (keyboard, mouse)
For example: Find any file with the file name "res" under/etc
Find/etc-name "Res. "
Find all folders under the/root directory
Find/root-type D
Multiple conditional queries can be added as-a or-o,-a equivalent and relationship,-o equivalent or
Find all files that are larger than 1024k in the/root directory and begin with a file name of VM
Find/root-size +1024k-a-name "VM. *"

Cat: Displaying and connecting the contents of a file
For example, view network card configuration
Cat/etc/sysconfig/network-scripts/ifcfg-eth0

MORE: Pagination View commands
Features like cat
More support for pipe breaks
For example
ls-lh/etc/*.conf | More

Head and tail View the beginning and end of a file
Parameters:
-N: View a few lines
For example, view the commands in the first four lines of the head-4/etc/passwd file.
-F: Use the end of dynamic trace file with tail
Tail-f/var/log/messages

WC: Statistics The amount of words in the contents of the file, the number of lines, and other information.
Parameters:
-C: The number of bytes in the file contents
-L: Number of rows in the statistics file
-W: Count the number of words in the content
Example: Query/etc/passwd number of rows wc-l/etc/passwd
Can be used in conjunction with other commands
For example, see how many. conf files are in/etc: Find/etc-name "*.conf" | Wc-l
If you do not enter parameters, they are automatically arranged in the order of-c-l-w.

Linux basic commands (partial)