Download Linux Basic Commands: Functionality and Syntax and more Exercises Computer Fundamentals in PDF only on Docsity!
1.ls -l for listing the files as well as directories those are kept in the particular working directory syntax [root@nettech root]#ls -l
2.ls -la same as 'ls -l'but by this command we can also see the hiden files. syntax [root@nettech root]#ls -la
3.ls -li same as 'ls -la' but it will also shows us the inode number of each and every file syntax [root@nettech root]#ls -li
4.ls by this command we can see only file name nothing else syntax [root@nettech root]#ls
5.clear it will clear the screen(short cut ctl+l) syntax [root@nettech root]#clear
6.exit to end a current session as well current terminal logging syntax [root@nettech root]exit
7.touch to create a new empty file syntax [root@nettech root]#touch
8.cd to change the working/present directory syntax [root@nettech root]#cd /home/mango where '/home/mango' is the desired directory to be change from '/root'
9.cat to view the contents of a file and it is also used for creating a new file with some contents syntax [root@nettech root]#cat to view file contents [root@nettech root]#cat > newfilename enter,then you can write something in the file and then to save the file contents press clt+d then enter
10.mkdir to make a new directory syntax [root@nettech root]#mkdir newdirname you can also create a directory at your desired path without changing your present working directory syntax [root@nettech root]#mkdir /home/mango/newdirname
11.rm to remove a empty file syntax [root@nettech root]#rm filename
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12.rmdir to remove a empty directory syntax [root@nettech root]#rmdir directoryname
13.rm [-i/-r/-f] to remove a directory with its subdirectories as well as its files that is to remove a directory which already contains some files in it syntax [root@nettech root]#rm -i directory/filename -i stands for interactively -r stands for recursively -f stands for forcefully 14.cp to copy something in a destination file or directory syntax [root@nettech root]#cp sourcepath destinationpath example: [root@nettech root]#cp /home/mango/webmin.rpm /root/abcd in this example the webmin.rpm file will be copied in /root/abcd directory
15.mv to move one file or directory from one place to another place, it is also used for renaming adirectory or file syntax [root@nettech root]#mv source destination [root@nettech root]#mv oldfilename newfilename [to change the file name]
16.man to view the mannual page of commands for syntax syntax [root@nettech root]#man commandname
17.info to view the information about any command syntax [root@nettech root]#mkdir info
18.--help to view the help doccuments of a command syntax [root@nettech root]#commandname --help
19.dir to view the subdirectories and filesn under the directory syntax [root@nettech root]#dir
20.su - to become a super user syntax [mango@nettech mango]$su - output wil be [root@nettech root#]
21.who by this command you can see the user name and their ip addresses who have loged in on your server syntax [root@nettech root]#who
22.whoami this command shows your current logged in terminal user name syntax [root@nettech root]#whoami
23.who am i this command shows you the logged in terminal number and user name and more detailed information Page 2
34.groupadd to add a new group syntax [root@nettech root]#groupadd groupname
35.gruopdel to delete a group syntax [root@nettech root]#groupdel groupname
36.chown to change the ownership of a file or directory syntax [root@nettech root]#chown ownername filename example: [root@nettech /]#ls -l output drwxrw-rw- 2 root root 4096 Mar 11 12:03 abcd (permission) (own) (group own)(size) (name)
[root@nettech root]#chown tarun /abcd in this example /abcd directory owner will be change to tarun user effect [root@nettech /]#ls -l drwxrw-rw- 2 tarun root 4096 Mar 11 12:03 abcd
37.chgrp to change the group ownership of a file or directory syntax [root@nettec root]#chgrp newgroupownername filename example [root@nettech /]#ls -l drwxrw-rw- 2 tarun root 4096 Mar 11 12:03 abcd [root@nettech root]#chgrp tarun /abcd effect [root@nettech /]#ls -l drwxrw-rw- 2 tarun tarun 4096 Mar 11 12:03 abcd
38.chmod to change the permission of a file or directory drwxrw-rw- 2 root root 4096 Mar 11 12:03 abcd (permission) (ownr) (grpownr) (size) (name) IN OCTAL VALUE d stands for directiry READ= r stands for read only permission WRITE= w stands for write only permission EXECUTE= x stands for execute only permission drwxrw-rw- FIRST OCTET FOR DENOTING THE DIRECTORY OR FILE OR LINK FILE ETC. SECOND THREE OCTET FOR USER OR OWNER PERMISSION (rwx OR 7 IN OCTAL VALUE) THIRD THREE OCTET FOR GROUP PERMISSION (rw- OR 6 IN OCTAL VALUE)
FORTH THREE OCTET FOR OTHERS PERMISSION (rw- OR 6 IN OCTAL VALUE) SYNTAX [root@nettec root]#chmod value fileordirectoryname example
[root@nettech /]#ls -l drwxrw-rw- 2 tarun root 4096 Mar 11 12:03 abcd [root@nettech /]#chmod 402 /abcd [root@nettech /]#ls -l drw-----w- 2 tarun tarun 4096 Mar 11 12:03 abcd
40.usermod to modify the user profile Page 4
synatx [root@nettech root]#usermod -parameter groupname username
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