Mr. Ugo Cupcic suggested that i should run
sudo chmod 777 /dev/rtc

And then i should be able to access the /dev/rtc as normal user.

What he suggested regarding changing permissions worked but i still get segmentation faults.The program stops after the client and the server are initialized.They never start communicating.

the following is the output i get currently:


UINodeRepository::Scan()
Scanning def /usr/lib/flowdesigner/toolbox
done loading def files
loading XML document from memory
done!
Building network  :MAIN
ROS node : HARK_MASTER_NODE generated...
node_RosAddHarkIntClient_1 constructor end...
node_RosAddHarkIntClient_1 initialized...
node_RosAddHarkIntServer_1 initialized...
ROS initialized...
Segmentation fault

From: Ashwin Kamath <ashwin24udp@yahoo.com>
To: Ros Mailing list <ros-users@code.ros.org>
Sent: Wednesday, 8 June 2011 11:29 AM
Subject: Error while running a simple server client program in flowdesigner

i am trying to run the following tutorial:http://winnie.kuis. kyoto-u.ac.jp/HARK/wiki.cgi? page=HARK-ROS+Tutorial+2

but i get the following error and the program stops abruptly: 


[ INFO] [1307457046.525074887]: Connected to master at [localhost:11311] 
ROS node : HARK_MASTER_NODE generated... 
/dev/rtc: Permission denied 
Cannot open /dev/rtc 
ioctl: Bad file descriptor 
node_RosAddHarkIntClient_1 constructor end... 
node_RosAddHarkIntClient_1 initialized... 
node_RosAddHarkIntServer_1 initialized... 
ROS initialized... 
Segmentation fault 

since i was having issues with permissions i tried using sudo and ran the file in terminal,but i get the following error; 

ROS_ROOT is not set!  Using default rosconsole configuration values 
UINodeRepository::Scan() 
Scanning def /usr/lib/flowdesigner/toolbox 
done loading def files 
loading XML document from memory 
done! 
Building network  :MAIN 
[FATAL] [1307457375.864763327]: ROS_MASTER_URI is not defined in the environment. Either type the following or (preferrably) add this to your ~/.bashrc file in order set up your local machine as a ROS master: 

export ROS_MASTER_URI=http:// localhost:11311

then, type 'roscore' in another shell to actually launch the master program. 
[FATAL] [1307457375.864837707]: BREAKPOINT HIT 
        file = /tmp/buildd/ros-cturtle-ros-1. 2.6/debian/ros-cturtle-ros/ opt/ros/cturtle/ros/core/ roscpp/src/libros/master.cpp 
        line=70 

Trace/breakpoint trap 

i exported the ROS_MASTER_URI variable in the .bashrc file and started roscore in a new terminal.but the result is same.i still get the same error.Can some one please tell me how to resolve this issue.