Basic Linux Commands

Viewing, copying, moving and deleting files

 ls  Display the contents of the current directory
 ls -a  Display also hidden files and hidden directories
 cp filename /path/dir_name  Copy filename into directory /path/dir_name
 cp -r dir_name /path/dir_name2  Copy the entire dir_name into /path/dir_name2
 cp filename1 filename2 /path/dir_name  Copy filename1 and filename2 into /path/dir_name
 rm name  Remove a file or directory called name
 rm -r name  Remove an entire directory as well as its included files and subdirectories
 mv filename /path/dir_name  Move filename into /path/dir_name
 mv filename1 filename2  Rename filename1 to filename2
 cat filename  Display filenames contents
 more filename  Display filename in pages. Use spacebar to view next page
 head filename  Display filenames first 10 lines
 head -15 filename  Display filenames first 15 lines
 tail filename  Display filenames last 10 lines
 tail -15 filename  Display filenames last 15 lines
 pwd  Display current directory
 cd /path/dir_name  Change to directory /path/dir_name
 cd ..  Go 1 directory up
 mkdir dir_name  Create directory dir_name
 rmdir dir_name  Delete directory dir_name


Finding files and text within files

updatedb Update (create first time used) a database ofall files under the root directory /
locate filename Find file filename searching in the database
find / -name filename Starting from the root directory search for the file called filename
find / -name *filename Same as above but search for file containing the string filename
grep string /path/dir_name Starting from /path/dir_name search for all files containing string
which application_name Search $path for application app_name
whereis application_name Search $path, man pages and source files for application_name


Archived files


tar -xzf filename.tgz Decompress tzg file
tar -xzf filename.tar.gz Decompress tar.gz file
tar -xjf filename.tar.bz2 Decompress tar.bz2 file


tar -czf filename.tar /path/dir_name Compress directory /path/dir_name to filename.tar
gzip -c filename > filename.gz Compress /path/dir_name to filename.tar.gz
bzip2 -c filename > filename.bz2 Compress /path/dir_name to filename.tar.bz2


Using rpm files

rpm -hiv package.rpm Install rpm called package.rpm
rpm -hiv –force package.rpm Install rpm called package.rpm by force
rpm -hUv package.rpm Upgrade rpm called package.rpm
rpm -e package.rpm Delete rpm called package.rpm
rpm -qpil package.rpm List files in not-installed rpm called package.rpm
rpm -ql package.rpm List files in installed rpm called package.rpm
rpm -q str List installed rpms containing the string str
rpm -qf /path/application_name Display the rpm that contains application application_name


 Starting and Stoping

startx Start the X system
shutdown -h now Shutdown the system now and do not reboot
halt Same as above
shutdown -r now Reboot
reboot Same as above
shutdown -r +10 Reboot in 10 minutes


 Mounting filesystems

mount -t vfat /dev/sd(a)(1) /mnt/c_drive Mount the first partition 1 of the first hard disk drive a which is in fat32 vfat dormat under /mnt/c_drive directory
mount -t iso9660 /dev/cdrom /mnt/cdrom Mount cdrom under /mnt/cdrom directory
umount /mnt/hda1 Unmout the above


User Administration

users Display users currently logged in
adduser username Create a new user called username
passwd username Define password for user called username
who List logged-in users
whoami Display current user
finger username Displays info about user username
su Log in as root from current login
su – Log in as root from current login and take root’s path
exit Exit from console login (ie, logout).



command Execute command in the foreground
command & Execute command in the background
ctrl+z Suspend a program
ctrl+c Interrupt a program
ps List all processes
kill -9 pid Kill process with id pid
top Monitor processes in real time



hostname List the system’s hostname
ifconfig Set/Display network information
host ip Resolves ip’s hostname
ping ip/hostname Check if ip/hostname is reachable
traceroute ip/hostname Find network path to ip/hostname


 System Information

uname -a General system information
fdisk -l List partition tables
cp filename /path/dir_name Copy filename into directory /path/dir_name
df -T -h List filesystem disk space usage
lspci List PCI devices
lsusb List USB devices
free -m Display RAM+Swap usage


 Program Compile

gcc -o output file.c Compile a C program
./output Run a C program you have compiled
g++ -o output file.cpp Compile a C++ program
./output Run a C++ program you have compiled
./configure && make && su -c ‘make install’ Configure, compile and install a program with Makefile