Chris Murphy wrote:
It's not really workable without an atomic and out of tree
method, otherwise libraries are still yanked out from under running
processes at some point.
Running programs and their loaded libraries count as open files. Unixy
filesystems don't delete open files. They change the directory entry to
point to the new file and keep the old file around until it's closed.
Therefore libraries are *not* yanked out from under running processes.
What tends to break is badly designed GUI programs that apparently
don't keep their files open but still expect different files to be from
the exact same version. Firefox and Seamonkey seem to do something like
that. They tend to break in funny ways when updated. Many other GUI
programs have no problems with getting updated while running.