Dynamically changing window size

Hello everyone:
    
           Thanks a lots, I have received several replies for the problem
with regarding to resizing the window from grass environment. I appreciate
those very much. Now we can dynamically change the value
of the XDRIVER_* by using the g.gisenv command. However, I am having trouble
in getting GRASS to adopt the new values, i.e., though the values of the
XDRIVER_* changed, they are not available to the environment, unless I quit
from grass and reactivate it. Please send
me your suggestion. Thank you in advance.

        zhian li