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6.5 KiB
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Basic Linux Commands |
Basic Linux Commands
When starting out with linux, there are some basic commands everyone should know.
1. cd - change directory
- cd followed by a directory or file path will take you inside that directory(folder).
2. ls - list command
- Type
ls
and the contents of the current directory will be displayed. - Two common flags used with
ls
are-l
and-a
, they can be used together and chained as such:ls -la
. The-l
flag will show you files in list order and in long format including a display of permissions,-a
will show dot type files which are typically hidden in a GUI file finder such as.env
files - Flag ordering does not matter, so the previous command could be written as
ls -al
3. man - manual command
- Shows you the manual for the following command. This is very helpful when trying to figure out how an unfamiliar command works. For example, type
man ls
for everything you need to know about the ls command. Typeq
to exit.
4. pwd - path
- Type
pwd
to display the path to your current directory.
5. mkdir - make directory
- This command, followed by the name you wish to name your directory, creates a new directory.
mkdir folder1
will make a new directory called folder1.
6. rmdir - remove directory
- Removes the directory that follows the command.
rmdir folder1
will delete the directory named folder1 if it exists.
7. rm - remove
- This command removes files, not directories.
rm file.txt
will remove the file named file.txt as long as it exists and is in the current directory. - Warning, this command is capable of destroying entire systems, use with caution
8. touch - creates file
- The
touch
command is used to create a file. It can be anything, from an empty txt file to an empty zip file. 'touch new.txt' will create a new file with name new.
9. mv - move
- Use the
mv
command to move files through the command line. We can also use the mv command to rename a file. For example, if we want to rename the file “text” to “new”, we can use 'mv text new'. - Warning, this command is capable of destroying entire systems, use with caution
10. right-click - copy and paste
- This one is less of a command and more of a how-to, however, it is very useful for doing almost anything in a terminal on linux. To begin, highlight text like normal and then "right-click" on your mouse to copy a selection. You should see the highlighted portion become un-highlighted, this means you copied the selection. Now "right-click" on where you want to paste the selection and you're done.
11. less - view file content
- Use
less filename.txt
to view contents of a file and navigate through them. By default, less will go through the file page by page.
- cat - display file's textual contents
- Use this command to display text from within a given file on your terminal. Entering
cat myFile.txt
in your terminal will display the contents of the filemyFile.txt
on screen. Thecat
command can be a very handy tool when used with the terminal pipes.
- clear - clear terminal
- Use
clear
to simply clear all output from your terminal.
- cp - copy files and directories
- Use
cp
to copy a file or a direcotry with files inside it to another location using commandcp CURRENT_FILE-LOCATION DESTINATION_FOLDER
. Add-r
flag to copy a directory that is not empty.
- top - shows the system load
- Use
top
to get information about running processes of your system, the amount or RAM they allocate and the CPU percentage that they use. 'Top' is interactive so do not forget to pressq
when you want to quit.
- df -h Checks disk space in human readable form
- Shows the size, amount used, amount available and capacity percentage of mounted drives/partitions.
- grep - The grep searches any given input files, selecting lines that match one or more patterns.
- use
grep
to find a file, a directory, some text in the file/directory.
Example:
$ ps ax | grep -w login
25291 s000 Ss 0:00.11 login -pf <user>
25467 s000 R+ 0:00.00 grep -w login
25409 s004 Ss 0:00.04 login -pf <user>
- sudo - execute a command as super user
- A widely used command in the Linux command line, sudo stands for "SuperUser Do". So, if you want any command to be done with administrative or root privileges, you can use the sudo command.
- kill - stops runing process
- The
kill
command sends a signal to a running process. This default action normally stops processes. If you want to stop a process, specify the process ID (PID) in theProcessID
variable. The shell reports the PID of each process that is running in the background (unless you start more than one process in a pipeline, in which case the shell reports the number of the last process). You can also use theps
command to find the process ID number of commands.
- find - search for files in a directory hierarchy
find
searches the directory tree rooted at each given file name by evaluating the given expression from left to right, according to the rules of precedence, until the outcome is known (the left hand side is false for and operations, true for or), at which pointfind
moves on to the next file name.
- grep - print lines matching a pattern
grep
searches forPATTERN
in each FILE. A FILE of“-”
stands for standard input. If no FILE is given, recursive searches examine the working directory, and nonrecursive searches read standard input. By default,grep
prints the matching lines.
- man - Show the manual for a command
- Use
man
to see manual of any commmand. It will show different ways a given command can be used
Example:man ls
- ps - Show active processes
- Use
ps
to see running processes, and their process IDs
Example:ps
- history
- Use
history
to see previously entered commands
Example:history
- grep
- Use
grep
to match on specific keyword(s)
Example:history | grep ls
will show all commands from history containingls
Useful Resources for Practice:
- JSLinux: Run the terminal inside your browser. Great for practice.
- LearnShell: Interactive Linux shell (terminal) tutorials.
- LinuxJourney: A collection of beginner-friendly terminal tutorials.