unattended aptitude

[Pierre Frenkiel <pierre.frenkiel@gmail.com>]

hi,
I would like run "aptitude safe-upgrade" without staying in front of my
screen for hours
A convenient way would be to postpone to the end of the upgrade all
package installs needing an answer, like

 ==> File on system created by you or by a script.
 ==> File also in package provided by package maintainer.
   What would you like to do about it ?

but I don't see any way to do that(it would be nice to have
such an option in aptitude...)

An other solution is to use the -y flag, but in that case it's
the package maintainer's file  which is installed.
Is there a way to run aptitude with "N" as automatic answer?
May-be redirecting input from a file with several "N" lines ?

best regards,
--
Pierre Frenkiel