Re: Fonctionnalités clées.

Ces fonctionnalités ont des équivalents sous d'autres OS

Vraiment ? (mythe 15 et 16) Même les control groups ?

Et est-ce vraiment utile de rendre systemd portable, avec toute la complexité associée, quand ça n'intéresse personne (par exemple, chez *BSD) ?

Myth: systemd could be ported to other kernels if its maintainers just wanted to.

That is simply not true. Porting systemd to other kernel is not feasible. We just use too many Linux-specific interfaces. For a few one might find replacements on other kernels, some features one might want to turn off, but for most this is nor really possible. Here's a small, very incomprehensive list: cgroups, fanotify, umount2(), /proc/self/mountinfo (including notification), /dev/swaps (same), udev, netlink, the structure of /sys, /proc/$PID/comm, /proc/$PID/cmdline, /proc/$PID/loginuid, /proc/$PID/stat, /proc/$PID/session, /proc/$PID/exe, /proc/$PID/fd, tmpfs, devtmpfs, capabilities, namespaces of all kinds, various prctl()s, numerous ioctls, the mount() system call and its semantics, selinux, audit, inotify, statfs, O_DIRECTORY, O_NOATIME, /proc/$PID/root, waitid(), SCM_CREDENTIALS, SCM_RIGHTS, mkostemp(), /dev/input, ...

And no, if you look at this list and pick out the few where you can think of obvious counterparts on other kernels, then think again, and look at the others you didn't pick, and the complexity of replacing them.

Myth: systemd is not portable for no reason.

Non-sense! We use the Linux-specific functionality because we need it to implement what we want. Linux has so many features that UNIX/POSIX didn't have, and we want to empower the user with them. These features are incredibly useful, but only if they are actually exposed in a friendly way to the user, and that's what we do with systemd.

"Quand certains râlent contre systemd, d'autres s'attaquent aux vrais problèmes." (merci Sinma !)