Hi all, This email isn't a recommendation for the Devuan distribution, it's just some interesting info for the more DIY members of the Devuan community...
Consider the following: * Suckless init: http://git.suckless.org/sinit * Suckless svc: http://core.suckless.org/svc * Suckless portable utils (sbase): http://core.suckless.org/sbase * Suckless nonportable utils (ubase): http://core.suckless.org/ubase The init program does initialization with no process management. It passes control to rc.whatever. In that respect, it doesn't conform to Laurent's minimum of supervising at least one process, but rc.whatever can exec to something that manages all processes, so you have only that one tiny process at risk. The ubase utilities include something called "respawn", which apparently manages a process via fifo (http://git.suckless.org/ubase/tree/respawn.c). They have some shellscripts in the svc svc-master group, which appear to make for very simple init scripts. === MY PLANS === So what I'm going to do, when I get the time, is init a Linux box with Suckless init (http://git.suckless.org/sinit/tree/sinit.c), and have it transfer control to rc.whatever, which will be a tiny script using respawn to run all the rest of the process management, using respawn for early stuff, and daemontools or daemontools-encore for the rest. I've already done a proof of concept, I can init to /bin/bash using Suckless Init, and when I send the proper SIGUSR1, SIGCHLD, or SIGINT to PID1, it runs rc.shutdown with the expected arguments. Here's an example rc.shutdown: http://git.2f30.org/ports/tree/fs/bin/rc.shutdown The result will be very close to an init system as defined by Laurent: The only unmanaged process will be rc.whatever, and that will be a tiny script unlikely to abort by itself. If I *really* get into it, I think there might be a possibility of mixing the code of sinit.c with the code of respawn.c, to produce an init that *supervises* rc.whatever instead of just running it, with rc.whatever supervising and sub-supervising all the rest. What would make this challenging is that respawn.c (http://git.suckless.org/ubase/tree/respawn.c) depends on a fifo, and this might be before the root filesystem is mounted. Like I said before, I'm not advocating that Devuan put in any hooks or packages for this stuff, I'm just commenting on what's available for experimentation. SteveT Steve Litt May 2015 featured book: Quit Joblessness: Start Your Own Business http://www.troubleshooters.com/startbiz _______________________________________________ Dng mailing list Dng@lists.dyne.org https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng
