Question on set-window-margins

[Nicolas P. Rougier (inria)]

When I set margins on a window using 'set-window-margins', it 
works as expected until I switched to another buffer and margins 
are then reset to 0 on both sides. If I switch back to the 
original buffer, margins stay at 0. Does that mean that margins 
are not "attached" to the window nor to the buffer ?

The name of the function suggest it is attached to window (even 
though nothing is really specified in the documentation)  but I 
wonder if the 'set-window-margins' is actually meant to be 
transient ?

To keep margins attached to a buffer, I'm using the 
'window-state-change-hook' and a buffer local margin definition 
but maybe I missed a point.

Nicolas

--
Nicolas P. Rougier —— www.labri.fr/perso/nrougier
Institute of Neurodegenerative Diseases, Bordeaux