Useful Linux Commands — Files and Packages

John Au-Yeung - Feb 13 '21 - - Dev Community

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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.

head

The head command outputs the first few lines of a file.

The -n flag specifies how many lines to shows.

The default number of lines to show is 10.

tail

tail outputs the last few lines of a file.

We can also use the -n flag to specify how many lines to show.

Also, we can get the end of the file beginning with the N -th line with:

tail -n +N
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cat

cat concatenates list of files and send them to the standard output stream.

less

less is a quick tool to let us view a file.

It opens up the file content with a read-only window.

nano

nano is a small text editor.

It’s easy to use for beginners since we don’t have to learn lots of shortcuts.

nedit

nedit is a small graphical rextr editor.

And it lets us edit text with point and click, drag and drop, and syntax highlighting.

touch

touch lets us modify the timestamp of an existing file and quickly create a new file.

logout

logout lets us exit the shell we’re logged into.

ncdu

ncdu lets us display file space usage.

It opens a window that shows the disk usage of each file.

top

top displays all currently running processes and their owners, memory usage, and more.

htop

htop is an interactive version of top .

We can pass -u username to display processes that are owned by user username .

whereis

whereis lets is search for files related to a particular command.

For instance, we run:

whereis ls
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to find the path to the ls command and the associated manpage.

whatis

whatis prints the description of the command from its man page.

locate

The locate command finds a file anywhere in the system by searching a cached list of files.

find

find iterates through the file system to find the file we’re looking for.

It looks at files that currently exist in the system.

find lets us search by file age, size, ownership, type, timestamp, permissions, depth within the file system, regex, and more.

wget

wget lets us download a file from the Internet

curl

curl can be used like wget , but we need the --output flag.

curl supports many moe protocols and it’s more widely available that wget .

wget can only receive data, but curl can also send data.

wget can download files recursively, but curl can’t.

apt

The apt command is available in Debian based distros.

It can be used to install, upgrade, or delete software on our machine.

We can run apt search to search for packages. apt install lets us install packages.

Conclusion

Linux distros comes with many commands that we can use to manage files and download files.

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