Download Tightvnc from click here
1.Go to: System => Preferences => Remote Desktop
Check the boxes Allow other users to view your desktop and Allow other users to control your desktop, Also don't forget to set a desktop for security reasons.
2.Now you just need to know the ip-address your Ubuntu machine uses. To do this right click the icon with the two displays in your systray and click Connection information.
3.Now able to connect to your Ubuntu machine using a VNC client
4.If you want to connect to your PC outside your network you will need to know your routers outside ip-address and make a port forward in your router to your Ubuntu machine using port: 5900. You can use this website to obtain your outside ipaddress : whatismyip.com.
(Note : if you have a static ip no need of port forwarding)
Tuesday, June 2, 2009
Enable Remote desktop in Ubuntu
Remote GUI administration of linux system in windows
Installing Xming on Windows
In order to do X11 on Microsoft Windows, you need to install "X Server" software on the Windows box. You'll want to download and install both Xming and Xming-fonts.
Configuration of sshd and X11
In order for the local X Server (Xming - running on your Windows system) to talk to the remote Linux server, you'll need to verify some settings on the Linux server. First up is configuration of the sshd daemon (typically /etc/ssh/sshd_config for OpenSSH). Look for the following 2 lines and make sure they are configured correctly:
X11Forwarding yes
#X11UseLocalhost yes
By default, OpenSSH ships with X11Forwarding set to "no" but the default for X11UseLocalhost is "yes". So you should only have to add the "X11Forwarding yes" line.
Create a PuTTY session
a PuTTY public-key pair. If you need to install a generated PuTTY key (maybe you want to use a separate PuTTY key for X11 forwarding), then here are the directions for OpenSSH.
(login as yourself or as root and then "su" to your username)
# cd ~/.ssh
# cat > machinename@svn.pub
(paste in PuTTY key)
# ssh-keygen -i -f machinename@svn.pub >> authorized_keys
(Ctrl-D to exit)
1. Right-click on the Pageant icon in the system tray and choose "New Session".
2. Enter the hostname (i.e. 192.168.1.1)
3. Go to the Connection -> SSH -> X11 tab
4. Turn ON "X11 forwarding"
5. Display location should be: localhost:0
6. Go back to the Session tab
7. Enter a name in the Saved Sessions text box (i.e. "MyHost-X11") and click on "Save"
8. Click the "Open" button to connect to the server
If all goes well, you should see a line like:
/usr/bin/xauth: creating new authority file /home/thomas/.Xauthority
Which tells us that SSH is ready to do some X forwarding.
Fire up Xming
If you haven't already ran Xming you should run XLaunch and just roll through the defaults. Now, in the PuTTY window that is sitting at a command prompt, try:
# xeyes
And you should see the xeyes application open up on your Windows system. If you want to continue to start up other X applications, put an ampersand (&) at the end of the line.
More advanced stuff
1. Fire up XLaunch
2. Select "One window" and click "Next"
3. Select "Start a program" and click "Next"
4. The start program should be either "gnome-session" or "startkde"
5. Select Run Remote using PuTTY (plink.exe) and turn on the compression option.
6. Enter the IP address or hostname in "Connect to computer" of the Linux box that you are connecting to
7. Enter your username in the "Login as user"
8. Click the "Next" button
9. In the "Additional parameters", enter "-screen 0 1024 768" which will set screen zero to be 1024x768
10. If you run your SSH server on a non-standard port, enter "-P port" in the PuTTY extra options field (run "plink" at a Windows command prompt to see the possible options)
11. Save your configuration file and click "Finish"
Sunday, May 31, 2009
Quick reference Linux commands
alias - Create an alias
awk - Find and Replace text, database sort/validate/index
break - Exit from a loop
builtin - Run a shell builtin
cal - Display a calendar
cse - Conditionally perform a command
cat - Display the contents of a file
cd - Change Directory
cfdisk - Partition table manipulator for Linux
chgrp - Change group ownership
chmod - Change access permissions
chown - Change file owner and group
chroot - Run a command with a different root directory
cksum - Print CRC checksum and byte counts clear Clear terminal screen
cmp - Compare two files
comm - Compare two sorted files line by line
command - Run a command - ignoring shell functions
continue - Resume the next iteration of a loop
cp - Copy one or more files to another location
cron - Daemon to execute scheduled commands
crontab - Schedule a command to run at a later time
csplit - Split a file into context-determined pieces
cut - Divide a file into several parts
date - Display or change the date & time
dc - Desk Calculator
dd - Data Dump - Convert and copy a file
declare - Declare variables and give them attributes
df - Display free disk space
diff - Display the differences between two files
diff3 - Show differences among three files
dir - Briefly list directory contents
dircolors - Colour setup for `ls'
dirname - Convert a full pathname to just a path
dirs - Display list of remembered directories
du - Estimate file space usage
echo - Display message on screen ed A line-oriented text editor (edlin)
egrep - Search file(s) for lines that match an extended expression eject Eject CD-ROM
enable - Enable and disable builtin shell commands
env - Display, set, or remove environment variables
eval - Evaluate several commands/arguments
exec - Execute a command exit Exit the shell
expand - Convert tabs to spaces
export - Set an environment variable
expr - Evaluate expressions
factor - Print prime factors
false - Do nothing, unsuccessfully
fdformat - Low-level format a floppy disk
fdisk - Partition table manipulator for Linux
fgrep - Search file(s) for lines that match a fixed string
find - Search for files that meet a desired criteria
fmt - Reformat paragraph text
fold - Wrap text to fit a specified width.
for - Expand words, and execute commands format Format disks or tapes free Display memory usage
fsck - Filesystem consistency check and repair.
function - Define Function Macros
gawk - Find and Replace text within file(s)
getopts - Parse positional parameters
grep - Search file(s) for lines that match a given pattern
groups - Print group names a user is in
gzip - Compress or decompress named file(s)
hash - Remember the full pathname of a name argument
head - Output the first part of file(s)
history - Command History
hostname - Print or set system name
id - Print user and group id's
if - Conditionally perform a command
import - Capture an X server screen and save the image to file
info - Help info
install - Copy files and set attributes
join - Join lines on a common field
kill - Stop a process from running
less - Display output one screen at a time
let - Perform arithmetic on shell variables
ln - Make links between files
local - Create variables
locate - Find files
logname - Print current login name
logout - Exit a login shell
lpc - Line printer control program
lpr - Off line print lprint Print a file lprintd Abort a print job lprintq List the print queue
lprm - Remove jobs from the print queue
ls - List information about file(s)
m4 - Macro processor
man - Help manual
mkdir - Create new folder(s)
mkfifo - Make FIFOs (named pipes)
mknod - Make block or character special files
more - Display output one screen at a time
mount - Mount a file system
mtools - Manipulate MS-DOS files
mv - Move or rename files or directories
nice - Set the priority of a command or job
nl - Number lines and write files
nohup - Run a command immune to hangups
passwd - Modify a user password
paste - Merge lines of files pathchk Check file name portability
popd - Restore the previous value of the current directory
pr - Convert text files for printing printcap Printer capability database printenv Print environment variables
printf - Format and print data
ps - Process status
pushd - Save and then change the current directory
pwd - Print Working Directory
quota - Display disk usage and limits
quotacheck - Scan a file system for disk usage
quotactl - Set disk quotas
ram - ram disk device
rcp - Copy files between two machines.
read - read a line from standard input
readonly - Mark variables/functions as readonly remsync Synchronize remote files via email
return - Exit a shell function
rm - Remove files
rmdir - Remove folder(s)
rpm - Remote Package Manager
rsync - Remote file copy (Synchronize file trees) screen Terminal window manager
sdiff - Merge two files interactively
sed - Stream Editor
select - Accept keyboard input
seq - Print numeric sequences
set - Manipulate shell variables and functions
shift - Shift positional parameters
shopt - Shell Options
shutdown - Shutdown or restart linux
sleep - Delay for a specified time
sort - Sort text files
source - Run commands from a file `.'
split - Split a file into fixed-size pieces
su - Substitute user identity
sum - Print a checksum for a file
symlink - Make a new name for a file
sync - Synchronize data on disk with memory
tac - Concatenate and write files in reverse
tail - Output the last part of files
tar - Tape ARchiver
tee - Redirect output to multiple files
test - Evaluate a conditional expression
time - Measure Program Resource Use
times - User and system times
touch - Change file timestamps
top - List processes running on the system
traceroute - Trace Route to Host trap Run a command when a signal is set(bourne)
tr - Translate, squeeze, and/or delete characters
true - Do nothing, successfully
tsort - Topological sort
tty - Print filename of terminal on stdin
type - Describe a command
ulimit - Limit user resources
umask - Users file creation mask umount Unmount a device
unalias - Remove an alias
uname - Print system information
unexpand - Convert spaces to tabs
un
iq - Uniquify files
units - Convert units from one scale to another
unset - Remove variable or function names
unshar - Unpack shell archive scripts
until - Execute commands (until error)
useradd - Create new user account
usermod - Modify user account
users - List users currently logged in
uuencode - Encode a binary file
uudecode - Decode a file created by uuencode v Verbosely list directory contents (`ls -l -b') vdir Verbosely list directory contents (`ls -l -b')
watch - Execute/display a program periodically
wc - Print byte, word, and line counts
whereis - Report all known instances of a command
which - Locate a program file in the user's path.
while - Execute commands
who - Print all usernames currently logged in whoami Print the current user id and name (`id -un')
xargs - Execute utility, passing constructed argument list(s)
yes - Print a string until interrupted
.period - Run commands from a file
Start GUI from Linux/UNIX Shell
start the GUI Windows if you have KDE or Gnome installed in unix/linux
unix command for gui ---> xinit &
Linux command for gui ----->startx
Gnome based linux ---------------->gnome&
KDE based linux ------------------------------->kde&
Saturday, May 30, 2009
Ubuntu 9.04 (Jaunty Jackalope) is available for download
Ubuntu 9.04 for desktop, server and "netbook remix" is available for download
Ubuntu 9.04 includes the latest 2.6.28.8 kernel, and a host of features.
ubuntu 9.04 includes :- OpenOffice 3.0
- Latest Skype
- Latest Adobe Flash
- Faster boot times (reportedly as low as 25 seconds)
- Brasero 2.26 (all-in-one CD burning application)
1. GNOME 2.26
2. X.Org server 1.6
3. Wacom tablet hotplugging
4. New style for notifications and notification preferences
5. Boot performance
6. Linux kernel 2.6.28
7. Ext4 filesystem support
8. Cloud computing
9. Turn-key mail servers
Link to download for desktop ubuntu 9.04
How to change the root password if you forget in freeBSD
1.Reboot the the desktop or workstation
2.open in single user mode using
tyoe in the prompt $ boot -s
3.next run the fsck -p / && mount -u /
4.it will ask for password there you can reset for root
5.after changing the password now you can restart
Network secuirty command "iptables" in unix/linux
Description :
Rules that allow packets to be filtered by the kernel are put in place by running the iptables command.
iptables [-t table] -[AD] chain rule-specification [options]
iptables [-t table] -I chain [rulenum] rule-specification [options]
iptables [-t table] -R chain rulenum rule-specification [options]
iptables [-t table] -D chain rulenum [options]
iptables [-t table] -[LFZ] [chain] [options]
iptables [-t table] -N chain
iptables [-t table] -X [chain]
iptables [-t table] -P chain target [options]
iptables [-t table] -E old-chain-name new-chain-name
to view the rules that are currently applied --------> iptables -L(it will list the rules)
rules to network packets that are either inbound (INPUT), outbound (OUTPUT), or being forwarded through your server (FORWARD)
some iptable rules
a server that will block every inbound connection
iptables -P INPUT DROP
it accepts all the output connections
iptables -P OUTPUT ACCEPT
it drops all the forwarding connections
iptables -P FORWARD DROP
it allows for internal host connectivity through local
iptables -A INPUT -i lo -j ACCEPT
it allows port 80 tcp requests that are inbound to also go through
iptables -A INPUT -i eth0 -p tcp --dport 80 -j ACCEPT
Using "Nmap" you can scan ports and services
Description : Nmap is a tool used for determining the hosts that are running and what services the hosts are running. Nmap can be a valuable diagnostic tool for network administrators
Once the network is charted out using tools like Lan MapShot, the Nmap can be used to determine the type of services and hosts running in the network.
Uses of Nmap
1. Determining open ports and services running in an host
2. Determine the Operating System running on a host
3. Alter the source IP of the scan
nmap commands
-sS syn scan instead of a tcp scan
-O OS
examples how to run nmap
nmap -sS -O xxx.xxx.xxx.xxx ( x means ip or you can give hostname)
Friday, May 29, 2009
Installing google chrome in ubuntu
you can check the wine version using the following command
wine --version
If you want to install google chrome you need to have "wine ".You need to make sure wine version is 1.1.4
Google’s net-installer for Chrome doesn’t work in Wine. Instead, use the standalone installer.Download it from here
Now you need to Open a terminal to and change to the directory you downloaded the installer to. Run the installer with Wine using the following command
wine chrome_installer.exe
Now installation complete.Now you need to Start Google Chrome ,but it will crash for first time
chrome window should open, but will appear to be broken. Close Chrome.
Run Chrome with the–-new-http and –-in-process-plugins options to make it work
Run windows softwares in ubuntu
Install Wine to Enable you to run Windows software under Ubuntu Linux
run the command in the terminal
sudo apt-get install wine
Wine is installed in your home dir... it's in ~/.wine
Thursday, May 28, 2009
Graphics or resolution issue in ubuntu
There are two ways to troubleshoot graphics issue in ubuntu 8.04 hardy version
before running below command backup your xorg.config file in /etc/X11
first is to configuring the graphics one again using
in your terminal
1.sudo dpkg-reconfigure xserver-xorg
or
second one is to install nvidia setiings tools
in terminal
1.sudo apt-get install nvidia-settings
2.then run in terminal
sudo nvidia-xconfig
this fix your display issues
Note : some time above command screw up to bad display settings.be cautious before trying above commands
Changing themes in ubuntu ans some themes to download
Download the theme and extract it and you'll get a folder. Now open your Home Folder, press Ctrl+H to show hidden folders, open the .themes folder and paste the extracted folder in it. Now goto System->Preferences->Appearance and select the theme. If it does not appear in the list, press Customize button, click the Controls tab and select it from there.
Moomex-Theme
linkto download
no-name-jet
click here to download
Majestics
click here to download
Elegant for Rent
click here to download
Wednesday, May 27, 2009
Vista Fonts in Ubuntu
Installing Vista Fonts in Ubuntu
Linux Players List and how to install
Top Players in LINUX
1.VLC player
2.mplayer
3.xine
4.Kaffeine
5.totem
6.real player
Players Installation procedure follows:
1. VLC Media Player
VLC media player is a highly portable multimedia player for various audio and video formats (MPEG-1, MPEG-2, MPEG-4, DivX, mp3, ogg, …) as well as DVDs, VCDs
download vlc player
in Ubuntu
To install VLC, open a terminal and run following command:
sudo apt-get install vlc
in redhat
download vlc and open a terminal window and use the following command:
"yum install vlc"
2. MPlayer
Description:
It plays back CDs, DVDs, and VCDs. It also decodes multimedia files like AVI, MOV, WMV, and MP3 from local disk drives, and displays multimedia streamed over the Internet.
in ubuntu
Install mplayer using the following command
sudo apt-get install mplayer
other way to install players
download mplayer
./configure --enable-gui
note : ithout the --enable-gui switch, you'll get a command-line-based playermake
su (if you're not already root)
make install
3. Xine
Descrption :
It plays most MPEG/VOB, AVI, Ogg/OGM, VIVO, ASF/WMA/WMV, QT/MOV/MP4, RealMedia, Matroska, NUT, NuppelVideo, FLI, YUV4MPEG, FILM, RoQ, PVA files, supported by many native, XAnim, and Win32 DLL codecs. You can watch VideoCD, SVCD, DVD, 3ivx, DivX
In ubuntu
sudo aptitude install xine-ui libxine-extracodecs
in other linux flavors
your can download from the site
link to site
after downloading run below command in the terminal
yum install xine
4. Kaffeine
Description:
Kaffeine is a full featured Multimedia-Player for kde
In other flavors
click for kaffeine download
yum install kaffeine
5. Totem
Description:
GNOME desktop environment based on xine-lib or GStreamer. It features a playlist, a full-screen mode, seek and volume controls, as well as keyboard navigation
in Ubuntu
sudo apt-get install totem-gstreamer
in other flavors
yum install totem
6. Real player
Description:
Plays RealAudio, RealVideo, and now RealFlash
For all flavors download from
link to download
Prompt $ chmod +x Realplayer10Gold.bin
prompt$ ./Realplayer10Gold.bin
Some KDE player
Xt7-Player
KMPlayer
KMPlayer
M.O.V.E. (My Own Video Encoder)
MyRT
'Q' DVD-Author
Kdenlive
sMovieDB
SMPlayer
TCP/IP Network Configuration Files in UNIX/LINUX
For configuring the tcp/ip network you need to edit files in '/etc'
files follows
/etc/resolv.conf
/etc/hosts
Linux to first resolve a host name by looking at the local hosts file(/etc/hosts), then if the name is not found look to your DNS server as defined by /etc/resolv.conf
first we will edit /etc/resolv.conf
File: /etc/resolv.conf - host name resolver configuration file
search name-of-domain.com - Name of your domain or ISP's domain if using their name server nameserver 192.168.1.1 - IP address of primary name server
nameserver 192.168.1.2 - IP address of secondary name server
INFO ON resolv.conf: This configures Linux so that it knows which DNS server will be resolving domain names into IP addresses. If using DHCP client, this will automatically be sent to you by the ISP and loaded into this file as part of the DHCP protocol. If using a static IP address, ask the ISP or check another machine on your network
second we will edit /etc/hosts
File: /etc/hosts - locally resolve node names to IP addresses
127.0.0.1 localhost.localdomain localhost
192.168.19.167 node-name(its the system hostname)
INFO ON /etc/hosts : This informs Linux of local systems on the network which are not handled by the DNS server
NOTE : when adding hosts to this file, place the fully qualified name first.because it sendmail configure with hosts conf file.
Example of an "MOUNT" command in UNIX/LINUX
command : mount
descrption : Admin Attach (mount) a filesystem to an empty directory in order that the files therein may be accessed
example :
mount /dev/fd0 /mnt
Example of an "AWK" command in UNIX/LINUX
command : AWK
descrption : Filter Perform programmable text processing
example :
awk -f script.awk filename
Example of an "at" command in UNIX/LINUX
command : at
descrption : Schedule a series of commands to run at a particular time
example :
at 1430
> mount /dev/fd0 /mnt
> backup_script
> umount /dev/fd0
> Ctrl-d
Tuesday, May 26, 2009
unix/linux networking tutorial with what I think are some handy commands
1)Show the ethernet status
prompt $ ethtool eth0
2)Force 100Mbit Full duplex
prompt $ ethtool -s eth0 speed 100 duplex full
3)Blink the ethernet led
prompt $ ethtool -p eth0
4)Display all interfaces
prompt $ ip link show
5)Bring device up (or down)
prompt $ ip link set eth0 up
6)Display all IP addresses
prompt $ ip addr show
Unix Ebooks
Beginning Unix
Unix Power Tools, Third Edition
Hacking: The Art of Exploitation
Mac OS X Unix 101 Byte-Sized Projects
SSH, The Secure Shell: The Definitive Guide
HackNotes(tm) Linux and Unix Security Portable Reference
Implementing SSH: Strategies for Optimizing the Secure Shell
The Shellcoder's Handbook: Discovering and Exploiting Security Holes
Hacker's Challenge : Test Your Incident Response Skills Using 20 Scenarios
Migrating to the Solaris Operating System: The Discipline of UNIX-to-UNIX Migrations
http://rapidshare.com/files/227421925/ebook_Unix.Books.Collection.rar">clik here to download
Tips and Techniques for Everyday Use
Like a culinary cookbook, this book presents "recipes" for preparing or accomplishing a particular, specific thing. I've selected what I consider to be the easiest and most effective methods for accomplishing particular tasks, and have arranged these recipes in general sections according to subject matter -- the first part of the book is all about getting started, and contains the most essential information you need to know about using Linux; the remaining chapters deal with general categories of usage: Files, Text, Images, Sound, Productivity, and Networking.
click here for download
Linux 101 Hacks
There are total of 101 hacks in this book that will help you build a strong foundation in Linux. All the hacks in this book are explained with appropriate Linux command examples that are easy to follow.
This free eBook contains 12 chapters with total of 140 pages. Hacks mentioned in 6 chapters are based on the articles that I’ve already posted on my blog. Hacks mentioned in rest of the 6 chapters are brand new.
click here to download
Introduction to Linux
This guide was created as an overview of the Linux Operating System, geared toward new users as an exploration tour and getting started guide, with exercises at the end of each chapter. For more advanced trainees it can be a desktop reference, and a collection of the base knowledge needed to proceed with system and network administration. This book contains many real life examples derived from the author's experience as a Linux system and network administrator, trainer and consultant. We hope these examples will help you to
get a better understanding of the Linux system and that you feel encouraged to try out things on your own.
click this link to download
Linux Device Drivers
Third Edition of Linux Device Drivers, by Jonathan Corbet, Alessandro Rubini, and Greg Kroah-Hartman
click here to download
Saturday, May 23, 2009
Tuesday, May 19, 2009
What is an kernel
In computing, the kernel is the central component of most computer operating systems. Its responsibilities include managing the system's resources (the communication between hardware and software components).
1. As a basic component of an operating system, a kernel provides the lowest-level abstraction layer for the resources (especially memory, processors and I/O devices) that application software must control to perform its function. It typically makes these facilities available to application processes through inter-process communication mechanisms and system calls.These tasks are done differently by different kernels, depending on their design and implementation. While monolithic kernels will try to achieve these goals by executing all the code in the same address space to increase the performance of the system, microkernels run most of their services in user space, aiming to improve maintainability and modularity of the codebase.
2. A range of possibilities exists between these two extremes.
unix and linux difference
UNIX / Linux: That's a very broad question and could be answered any number of ways. Probably the simplest answer is that from a technical point of view there are no major differences. Most people aren't satisfied with believing that Linux and UNIX are very similar though. Here's a list of the most obvious remaining differences. Origin: UNIX originated in the laboratories of universities and large corporations as an initiative within the context of those organisations. Linux was begun by a university student (Linus Torvalds) without any initial support from any large organisation. Linux also began as in mimickry of other well-known UNIX-like implementations whereas the initial UNIX implementations were original research. Most commercial UNIX versions are also derived from that early research. Service Model: Most UNIX versions operate on the basis that you can buy help (support and service contracts). Although such things are increasingly available to Linux technologists traditional arrangements consist of providing your own help with the assistance of a community of like-minded people. Linux is big and access to communities is more important than say it is for IBM mainframes. Equipment: Although Linux runs on many kinds of equipment it is best known for its support of commodity IBM-Intel PC-based hardware. Most of the more popular UNIX flavours focus on high-performance hardware usually of a proprietory nature or using high-end standard computing architectures like SPRAC. With ever-increasing gains in pc-hardwarelike Serial-ATA this distinction is not as large as it used to be especially for low performance uses like desktops. Licensing: Linux follows the Free Software Foundation's radical licensing model which provides a great deal of liberty to those that interact with Linux technology. UNIX versions provided by other vendors have profit strategies embedded in them. People who offer Linux services might have a profit strategy but Linux itself doesn't. This means that vendor lock-in is less of an issue with Linux than it is with other UNIX offerings. It also means that organisations big enough to have a center of computing competancy always have the choice of doing it themselves. Honesty: Linux and related software is extremely visible. You can find out about flaws before yocommit to the technology rather than afterwards. Because of this a version number in Linux is a more relable indicator of the quality of the software than in UNIX. For example most Linux software spends a long time being version 0 (zero) before it ever qualifies for the label version 1. In terms of quality performance and feature set there's little to separate Linux from the other UNIXes. Linux has yet to provide genuine real-time scheduling which some other UNIX versions do well.
Saturday, May 16, 2009
commands du,df,
Command: du
This command prints the disk usage (in Kb) of each directory and it's sub
directories. By default it starts from the current directory, but supplying
the name of a directory after the command will make it start from that
directory.
Sunday, May 3, 2009
Changing file permissions
- chmod 755 file Changes the permissions of file to be rwx for the owner, and rx for the group and the world. (7 = rwx = 111 binary. 5 = r-x = 101 binary)
- chgrp user file Makes file belong to the group user.
- chown youself file Makes youself the owner of file.
- chown -R youself dir Makes youself the owner of dir and everything in its directory tree.
Changing file permissions and attributes
- chmod 755 file Changes the permissions of file to be rwx for the owner, and rx forthe group and the world. (7 = rwx = 111 binary. 5 = r-x = 101 binary)
- chgrp user file Makes file belong to the group user.
- chown yourself/othersname file Makes yourself/othersname the owner of file.
- chown -R yourself/othersname dir Makes cliff the owner of dir and everything in its directory tree.
You must be the owner/suoder of the file/directory before changing the file permissions
Basic Linux commands
Basic Linux Commands
1) man -This magic command brings up the online Unix manual.
2) ls-Lists files.
3) pwd-Shows present working directory
4) cd -Changes directories.
5)vi-An editing program
6) grep-Extracts information from files
7)chmod -Change file permissions.
8) rm -Delete file.
9)“cp” for copy
10)“mv” for move file
