Linux Commands
ls
- directory listingls -al
- Formatted listing with hidden filescd dir
- change directory to dircd
- change to homepwd
- show current directorymkdir dir
- create directory dirrm file
- delete filerm -r dir
- delete directory dirrm -f file
- force remove filerm -rf dir
- remove directory dircp file1 file2
- copy file1 to file2mv file1 file2
- rename file1 to file2ln -s file link
- create symbolic link 'link' to filetouch file
- create or update filecat > file
- place standard input into filemore file
- output the contents of the fileless file
- output the contents of the filehead file
- output first 10 lines of filetail file
- output last 10 lines of filetail -f file
- output contents of file as it growsssh user@host
- connect to host as userssh -p port user@host
- connect using port pssh -D port user@host
- connect and use bind port./configure
make
make install
ping host
- ping host 'host'whois domain
- get whois for domaindig domain
- get DNS for domaindig -x host
- reserve lookup hostwget file
- download filewget -c file
- continue stopped downloadwget -r url
- recursively download files from urldate
- show current date/timecal
- show this month's calendaruptime
- show uptimew
- display who is onlinewhoami
- who are you logged in asuname
- a - show kernel configurecat /proc/cpuinfo
- cpu infocat /proc/meminfo
- memory informationman command
- show manual for commanddf
- show disk usagedu
- show directory space usagegrep pattern files
- search for pattern in filesgrep -r pattern dir
- search recursively for pattern in dircommand I grep pattern
- search for for pattern in the output of commandlocate file
- find all instances of fileps
- display currently active processesps aux
- ps with a lot of detailkill pid
- kill process with pid 'pid'killall proc
- kill all processes named procbg
- lists stopped/background jobs, resume stopped job in the backgroundfg
- bring most recent job to foregroundfg n
- brings job n to foregroundchmod octal file
- change permisssion of file
4 - read(r)
2 - write(w)
1 - execute(x)
order :- owner/group/world
eg:
chmod 777
- rwx for everyone
chmod 755
- rw for owner, rx for group/world
tar cf file.tar files
- tar files into file.tartar xf file.tar
- untar into current directorytar tf file.tar
- show contents of archive
tar flags:
c - create archive j - bzip2 compression
t - tables of contents k - do not overrite
x - extract T - files from file
f - specifies filename w - ask for confirmation
z - use zip/gzip v - verbosegzip file
- compress file and rename to file.gzipgzip -d file.gz
- decompress file.gztar -czvf name-of-archive.tar.gz /path/to/directory-or-file
-
Compress an Entire Directory or a .tar.gz Single File
tar.gz flags:
c - Create an archive.
z - Compress the archive with gzip.
v - Display progress in the terminal while creating the archive, also known as “verbose” mode. The v is always optional in these commands, but it's helpful.
f - Allows you to specify the filename of the archive.tar -xzvf archive.tar.gz -C /destination
- Extract an Archivezip -r file.zip folder/ -x *media/* *.zip *.sql
- Exclude zip direcory and filectrl+c
- halts current commandctrl+z
- stops current commandfg
- resume stopped command in foregroundbg
- resume stopped command in backgroundctrl+d
- log out of current sessionctrl+w
- erases one word in current linesctrl+r
- reverse lookup of previous commands/bin/
: This contains commands used by a regular user./boot/
: The files required for the operating system startup are stored here./cdrom/
: When CD-ROM is mounted, the CD-ROM files are accessible here./dev/
: The device driver files are stored in this folder. These device driver files will point to hardware-related programs running in kernel./etc/
: This folder contains configuration files and startup scripts./home/
: This folder contains a home folder of all users except the administrator./lib/
: The library files are stored in this folder./media/
: External media such as a USB pen drive is mounted in this folder./opt/
: The optional packages are installed in this folder./proc/
: This contains files which give information about kernel and every process running in OS./root/
: This is the administrators home folder./sbin/
: This contains commands used by the administrator or root user./usr/
: This contains secondary programs, libraries, and documentation about user-related programs./var/
: This contains variable data such as http, tftp, and similar other./sys/
: This dynamically creates the sys files