Linux Commands

Linux Commands

File Commands

ls – directory listing

ls -al – formatted listing with hidden files

cd dir - change directory to dir

cd – change to home

pwd – show current directory

mkdir dir – create a directory dir

rm file – delete file

rm -r dir – delete directory dir

rm -f file – force remove file

rm -rf dir – force remove directory dir *

cp file1 file2 – copy file1 to file2

cp -r dir1 dir2 – copy dir1 to dir2; create dir2 if it

doesn't exist

mv file1 file2 – rename or move file1 to file2

if file2 is an existing directory, moves file1 into

directory file2

ln -s file link – create symbolic link link to file

touch file – create or update file

cat > file – places standard input into file

more file – output the contents of file

head file – output the first 10 lines of file

tail file – output the last 10 lines of file

tail -f file – output the contents of file as it

grows, starting with the last 10 lines 

Process Management

ps – display your currently active processes

top – display all running processes

kill pid – kill process id pid

killall proc – kill all processes named proc *

bg – lists stopped or background jobs; resume a

stopped job in the background

fg – brings the most recent job to foreground

fg n – brings job n to the foreground 

File Permissions

chmod octal file – change the permissions of file

to octal, which can be found separately for user,

group, and world by adding:

● 4 – read (r)

● 2 – write (w)

● 1 – execute (x)

Examples:

chmod 777 – read, write, execute for all

chmod 755 – rwx for owner, rx for group and world

For more options, see man chmod.