time-limited integer factorization

["Max A." <maxale@gmail.com>]

Dear pari-users,

Is there a way to perform integer factorizations in GP bounded in time?
Say, I want to factor a certain number but spend at most one hour. If
factorization is not finished within this time frame, I want to it to
return all found factors along with a composite co-factor.

P.S. This has to be done without any interaction from my side. My
program is looking for specific factors of a whole bunch of numbers,
some of which may be very hard to factor completely, and I don't want
to spend more than an hour on each number.

Thanks,
Max