The tar command:


 To tar all the files with extensions cpp and doc into a tar file 
called abc.tar do the following 
   	tar cvzf abc.tar *.cpp *.doc

 To tar all the files and the subdirectories of a directory called 
temp into a tar file named abc.tar do the following
	tar cvzf abc.tar temp

If you want to put abc.tar in a different directory, proceed abc.tar by 
the path of the directory. For example, if you are in directory called 
parent and you want to tar a directory called child and call the tar file 
abc.tar and put abc.tar in the subdirectory child, type
	tar cvzf child/abc.tar child

 To see the table of contents of the tar file abc.tar do the 
following:
	tar tzf abc.tar 

 To untar the file abc.tar, do the following:
	tar xvzf abc.tar


 To change the password on Unix, type: 
	passwd

 To check your quota on Unix, type: 
	quota -v

 To print using Unix, type: 
	lpr -Pprintername filename 

 To change the ownership of a file/directory called abc to NewOwner, 
do the following:
	chown NewOwner abc

 To change your "plan" file, type:
	pico .plan

 To change your "finger" information, type
	chfn

 To create a directory called abc:
	mkdir abc

 To remove an empty directory called abc:
	rmdir abc

 To remove a directory called abc and all of its contents:
	rm -rf abc

 Permissions for the web directory and all of its subdirectories:
	711

 Permissions for files on the website:
	744

 To find out which groups you belong to, type:
	groups

 To find out which groups a user called abc belongs to, type:
	groups abc

 To find out who are the members of a group called abc, type
	getent group abc

 To append the contents of file2 to file1, type
	cat file2 >> file1

 To list all files including hidden files whose names begin with a dot 
in the current directory and its subdirectories, and put the list in a file called t.txt, 
type:

	ls -la * >> t.txt

 To list all files in the current directory and its subdirectories and 
sort them by modification date, and put the list in a file called t.txt,
type:

        ls -lt * >> t.txt

 To search for a file called abc.txt in the current directory and all 
of its subdirectories, type
	find -name 'abc.txt'

 To search for a file whose name contains the substring abc in the 
current directory and all of its subdirectories, type
        find -name '*abc*'

 To search for a file whose size is greater than 300k in in the 
current directory and all of its subdirectories, type
        find -name '*' -size +300k

 To search for a file called abc.txt in the root and all
of its subdirectories, type
        find / -name 'abc.txt'