Unix Commands

[Aravapalli]

Environment Control
Command :-: Description
cd d:-: Change to directory d
mkdir d:-: Create new directory d
rmdir d:-: Remove directory d
mv f1 [f2...] d :-: Move file f to directory d
mv d1 d2:-: Rename directory d1 as d2
passwd:-: Change password
alias name1 name2:-: Create command alias (csh/tcsh)
alias name1="name2":-: Create command alias (ksh/bash)
unalias name1[na2...]:-: Remove command alias na
ssh nd:-: Login securely to remote node
exit:-: End terminal session
setenv name v:-: Set env var to value v (csh/tcsh)
export name="v":-: set environment variable to value v (ksh/bash)

[Aravapalli]

Output, Communication, & Help
lpr -P printer f
or
lp -d printer f:-: Output file f to line printer
script [f]:-: Save terminal session to f
exit:-: Stop saving terminal session
mailx username:-: Send mail to user
man name:-: Unix manual entry for name
Process Control
CTRL/c *:-: Interrupt processes
CTRL/s *:-: Stop screen scrolling
CTRL/q *:-: Resume screen output
sleep n :-: Sleep for n seconds
jobs :-: Print list of jobs
kill % :-: Kill job n
ps :-: Print process status stats
kill -9 n:-: Remove process n
CTRL/z * :-: Suspend current process
stop %n :-: Suspend background job n
cmmd& :-: Run cmmd in background
bg [%n] :-: Resume background job n
fg [%n] :-: Resume foreground job n
exit :-: Exit from shell

[macuser9214]

Thanks for the list. Might come in handy. I have to install linux again on my linux box, because I broke it (Uninstalled GNOME, thinking I could just use KDE, but it won't even let me log into KDE. GRRRR!

[cheater]

ls List all non hidden files in current directory
cd Change to home directory
cat f Display the contents of file f
updatedb Updates the database of files (used with locate)
locate f Search the computer for file f
touch f Create f if it doesn't exist. Otherwise, update the date modified property
nano Terminal based text editor
vi More advanced terminal based text editor
wget f Download the file at the URL f (Download from the web)

[Aravapalli]

Normally shells are interactive. It means shell accept command from you (via keyboard) and execute them. But if you use command one by one (sequence of 'n' number of commands) , the you can store this sequence of command to text file and tell the shell to execute this text file instead of entering the commands. This is know as shell script.

Shell script defined as:
"Shell Script is series of command written in plain text file. Shell script is just like batch file is MS-DOS but have more power than the MS-DOS batch file."

[Aravapalli]

Kernel is hart of Unix Os.

It manages resource of Unix Os. Resources means facilities available in Unix. For e.g. Facility to store data, print data on printer, memory, file management etc .

Kernel decides who will use this resource, for how long and when. It runs your programs (or set up to execute binary files).

The kernel acts as an intermediary between the computer hardware and various programs/application/shell.

It's Memory resident portion of Unix. It performance following task :-

• I/O management
• Process management
• Device management
• File management
• Memory management

[bhar123]

I have just started to learn unix nowadays. i find unix really interesting. please recommend some good books from which i can get good basic knowledge.

[cheater]

You really don't need books. All the info you need is online. A good way to get some knowledge is to read the man pages for commands. This will tell you all the options that you can use with each and every command.

[bhar123]

Ok .. let me learn it the way you suggested. I want to get good hands on in basic as well as some scripts in 6 months. i wanna become a core unix admin.

[Aravapalli]

UNIX / Linux Tutorial for Beginners
Unix Tutorial

this links will give you some basic idea and after this as our friend said do R&D by using man command.

wish you best of luck