On Tuesday 26 December 2006 6:55 pm, David Lang wrote: > > Worse, it's not always possible. If chroot() has happened since the program > > started, there may not _be_ a path to my current executable available from > > this process's current or root directories. > > does this even make sense (as a general purpose function)? if the executable > isn't available in your path it's likly that any config files it needs are > not available either.
For a statically linked busybox it makes sense, but you're right that a dynamically linked one is going to suck however you do it... I guess what I really want to do is promote a vfork() to a real fork() after the fact. Which sounds painful. For the daemonize() case I want to unblock the parent and have it exit. Too bad I can't call clone() with some kind of CLONE_VFORK_BACKWARDS so it blocks the child until the parent exits. (Hmmm... CLONE_STOPPED doesn't help, just moves the race...) For the "new process runs code out of this executable" case what I really want is an actual fork, hideously expensive as that is on nommu systems. (There are things I can do to minimize that.) Maybe I can call clone() directly on a nommu system to get it to fork, even when the C library hasn't got it? Hmmm... > for something like busybox/toolbox where you have different functions based > on the name used to execute the program, which name would you use? The one from argv[0]. (Notice how exec has a "path to executable" and then an argv array? Nobody said that the path to executable and argv[0] had to point to the same string...) Rob -- "Perfection is reached, not when there is no longer anything to add, but when there is no longer anything to take away." - Antoine de Saint-Exupery - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
