Gedit error in fedora14: failed to connect to the Session Manager (difference between the Su and Su-commands)

After Su to root was used just now, an error occurred when running the command gedit:

(Gedit: 7932): eggsmclient-warning **: failed to connect to the Session Manager: none of the authentication protocols specified are supported

**
Glib-gio: Error: gdbusconnection. C: 2270: initable_init: assertion failed: (connection-> initialization_error = NULL)

Abandoned (core dumped)

The reason is:

Su Can only switch to administrator user permissions, without the Administrator's login script and search path
Su-not only can switch to administrator permissions, but also use the administrator login script and search path

Solution: After using sudo gedit or Su-, there will be no error in gedit!

It seems that you have to keep learning ......