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Linux is an operating system that many developers will use.
Therefore, it’s a good idea to learn some Linux commands.
In this article, we’ll look at some useful Linux commands we should know.
less
The less
command lets us show the content of a file.
The general syntax is:
less <filename>
We can navigate with arrow keys.
Spacebar and b
navigates page by page.
/
lets us search for content.
?
search backward.
F
enters follow mode. When the file is changed, the changes are displayed live.
ctrl+c quits follow mode.
cp
cp
lets us move files and folders.
For instance, we run:
cp foo bar
to copy foo
to bar
.
We can also use it to copy folders with the -r
switch:
cp -r fruits cars
We move the fruits
folder contents to cars
.
mv
The mv
command lets us move files and folders.
For instance, we run:
mv foo bar
to move foo
to bar
.
We can move files into a folder with:
mv grape banana fruits
We move the grape
and banana
files to the fruits
folder.
ls
The ls
command lets us list files and folders.
We can list the content of a given folder with:
ls /bin
We can add the a
switch to show hidden files.
l
shows files permissions, file and folder sizes, and modified date time.
We run ls -al
to show all that info.
rmdir
The rmdir
command lets us remove a folder.
We run:
rmdir fruits
to remove the fruits
folder.
We can use it to remove multiple folders:
rmdir fruits cars
We remove the fruits
and cars
folders.
The folders we delete must be empty.
To delete non-empty folders, we run:
rm -rf fruits cars
-r
means recursive and f
means force.
pwd
pwd
shows the current working directory.
cd
cd
lets us change the current working directory.
For instance, we run:
cd fruits
to go to the fruits
folder.
cd ..
to move to the home folder.
cd ../cars
moves to the parent folder of cars
.
We can use absolute paths with cd
, so we run cd /etc
to go to the /etc
folder.
mkdir
mkdir
lets us create a folder.
For instance, we run:
mkdir cars
to create a cars
folder in the current working directory.
And we run:
mkdir dogs cars
to create the dogs
and cars
folders.
We can create multiple nested folders with the -p
switch:
mkdir -p fruits/apples
!!
!!
lets us run the last command.
; / && / &
;
lets us run one command after the other like:
ls; pwd
&&
runs multiple commands but the ones on the right won’t run if the left one fails.
&
lets us run multiple commands in parallel instead of waiting for the current one to finish before running the next one.
Conclusion
We can run commands to show file content and run multiple commands with some operators with Linux.