Hi to everyone,
                 I am new to ROS. I have installed ROS in ubuntu 10.04.I am
going through the tutorials.

In roswtf tutorial,
http://www.ros.org/wiki/ROS/Tutorials/Getting%20started%20with%20roswtf

When I run to check the installation,(roscore is not started)
$roscd
$roswtf
I got the following:

Stack: ros
[rosstack] opendir error [No such file or directory] while crawling
/opt/ros/boxturtle/stacks
================================================================================
Static checks summary:

Found 1 error(s).

ERROR Not all paths in ROS_PACKAGE_PATH
[/home/santhosh/ros-tutorials/ros_tutorials:/home/santhosh/ros-tutorials/ros_pkg_tutorials:/opt/ros/boxturtle/stacks]
point to an existing directory:
 * /opt/ros/boxturtle/stacks

================================================================================

ROS Master does not appear to be running.
Online graph checks will not be run.
ROS_MASTER_URI is [http://localhost:11311]

This is showing some error.
Can anyone find solution for this and help me?
Thanks in advance................