I have several packages that I need to support on both Electric and
Fuerte. This involves switching back and forth between those two
distributions.

That works better now, but some things about message generation still
confuse me.

 * Is the pip installed genmsg-0.1.5 package for Fuerte only, or is it
also a replacement for the Electric version?

 * Sometimes I stumble over message checksum incompatibilities when
running a combination of source built code and binary installs. Are
any of these genmsg_py.py versions likely to produce different
checksums?

 * It is tricky to get the "correct" $PATH set up for both distros.
What is the recommended $PATH and genmsg_py.py version?

~$ locate genmsg_py.py
/opt/ros/electric/stacks/ros_comm/clients/rospy/scripts/genmsg_py.py
/opt/ros/electric/stacks/ros_comm/clients/rospy/scripts/genmsg_py.pyc
/opt/ros/electric/stacks/ros_comm/clients/rospy/scripts/rosbuild2/genmsg_py.py
/opt/ros/electric/stacks/ros_comm/clients/rospy/scripts/rosbuild2/genmsg_py.pyc
/opt/ros/electric/stacks/ros_comm/test/test_rospy/test/test_genmsg_py.py
/opt/ros/electric/stacks/ros_comm/test/test_rospy/test/test_genmsg_py.pyc
/opt/ros/fuerte/bin/genmsg_py.py
/opt/ros/fuerte/share/genpy/bin/genmsg_py.py
/opt/ros/fuerte/share/rospy/rosbuild/scripts/genmsg_py.py
/opt/ros/unstable/stacks/ros_comm/clients/rospy/scripts/genmsg_py.py
/opt/ros/unstable/stacks/ros_comm/clients/rospy/scripts/genmsg_py.pyc
/opt/ros/unstable/stacks/ros_comm/clients/rospy/scripts/rosbuild2/genmsg_py.py
/opt/ros/unstable/stacks/ros_comm/clients/rospy/scripts/rosbuild2/genmsg_py.pyc
/opt/ros/unstable/stacks/ros_comm/test/test_rospy/test/test_genmsg_py.py
/opt/ros/unstable/stacks/ros_comm/test/test_rospy/test/test_genmsg_py.pyc
/usr/local/bin/genmsg_py.py

On Electric, I get this:
$ echo $PATH
/home/joq/ros/electric_art/utexas-art/stacks/art_vehicle/art_run/bin:/opt/ros/electric/ros/bin:/home/joq/bin:/usr/lib/lightdm/lightdm:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games
$ which genmsg_py.py
/usr/local/bin/genmsg_py.py

On Fuerte, I get this:
$ echo $PATH
/opt/ros/fuerte/share/ros/bin:/opt/ros/fuerte/bin:/home/joq/ros/fuerte_dev/utexas-art/stacks/art_vehicle/art_run/bin:/opt/ros/fuerte/share/ros/bin:/opt/ros/fuerte/bin:/home/joq/bin:/usr/lib/lightdm/lightdm:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games
$ which genmsg_py.py
/opt/ros/fuerte/bin/genmsg_py.py
-- 
 joq