Areas of responsibility are implemented by standalone mechanisms that compose to create the larger integrated system and can:
1) Run in isolation from their upstream dependents.
2) Be replaced individually.
And seriously, systemd isn't one single daemon either. It's a collection of daemons running that communicate over a common protocol. It isn't all-or-nothing, either. Only a few of the daemons are considered "core" and the rest are optional. And, because they use a common documented protocol, even the core components can be replaced. You don't hear about alternatives because nobody has really written any, but it doesn't in any way prevent you from doing it.
I think the legitimate concerns about systemd are things like losing portability of stuff like Gnome to BSD and systemd's short history, but it isn't one giant monolith executable or anything like people say.
What common protocol? Mac OS X doesn't have dbus. It recently acquired XPC, but XPC is NOT a system bus -- it's simply an IPC library. It's neither required, nor universally used, nor is it terminally glued to the remainder of the OS.
> You don't, for example, just replace launchd with some other init system.
You don't? Says who? All launchd does is serve as an inetd/cron-esque daemon. The system daemons themselves continue to vend standard sockets and mach ports, and launchd itself does not pervade their externally vended interface.
> You don't just say "hey, screw Aqua I want to use something else."
Actually, you can. The display stack is driven by IOKit; XDarwin can run directly atop said stack.
Likewise, none of the "Mac-like" features that you want -- for example, automatic network configuration -- rely on any sort of centralized entity that pervades all daemons. There's a seperate system -- SystemConfiguration -- that provides that functionality, abstracted through a set of well-defined APIs and modular and distinct from the remainder of the system.
> * It's a collection of daemons running that communicate over a common protocol.*
Hence it's really rather monolithic, because to play in the systemd universe, everything has to conform to systemd's tightly coupled design.
MacOS is quite tightly integrated, it's what Apple does. Darwin is a bit different, as it's much more BSD-ish; with that I agree. But MacOS is a lot of stuff on top of Darwin and replacing any part of that would require tons of very MacOS specific code to do. Apple most definitely does not intend for their users to be able to replace logind or Aqua or pretty much any core service.
Probably a better way to phrase it would be to consided how much effort it'd take to run Aqua on BSD. You'd have to port basically everything that is MacOS. To me, that is what a monolithic system means.
Yes and no. It's true that OSX uses a variety of separate daemons, that run in different pids.
However they are all "required", "packaged together", "part of one source tree" and "shipped by a single vendor". In this respect they are a lot like systemd.
In fact it is arguably a lot more integrated. Both Python and Ruby are OSX dependencies. systemd isn't even close to that much of a power-grab.
I'm just feeding a troll or someone who is really ignorant, but here I go.
No it isn't, and no you don't. Systemd is closely tied to some Linux-specific features, but it generally isn't part of the kernel. And you don't have to update the kernel in sync with systemd. Systemd lives in userland, by definition.
It does impose a minimum kernel version in order for systemd to work, which is something like 2.6.39 (May 2011 vintage). They have bumped up the minimum version a couple times as they needed new features, but you don't have to upgrade both together. I routinely upgrade one or the other separately on multiple systems and distros.
And it bears repeating again... systemd is not one single executable or process. And not all of the components are required, you can turn all but a few core ones off. And the core ones could be replaced if you wanted to, because there's a documented interface that you can implement.
Also, Vi, Python and Perl aren't "required" for GNU/Linux. They're common, but definitely not required. Vi is required if you want to comply with the Single Unix standard, but that is not the same thing. GNU/Linux just refers to pairing the Linux kernel with GNU userspace utilities; it doesn't necessarily dictate any specifics. There are further standards like LSB that attempt to do so but again not relevant. On top of that, Vi, Python and Perl aren't even GNU projects, which is true of a ton of other programs common in Linux distros, which is one reason I personally find the term "GNU/Linux" a bit onerous.
Quote from http://lists.freedesktop.org/archives/systemd-devel/2014-May...:
> > You update systemd but you don't update the kernel? How does that make > > any sense?
> > systemd and kernels are updated in lockstep (Lennart)
And it bears repeating again... systemd is not one single executable or process
https://news.ycombinator.com/item?id=8364318
Also, Vi, Python and Perl aren't "required" for GNU/Linux.
By that definition nothing is ever required. There's the same argument in my comment history, someone said, udev is not required for GNU/Linux. technically, chromium doesn't "require" blink. It's not required, you can use chromium and receive raw html, right? But in that case OSX doesn't "require" Python either, just delete the files, done :)
So again, I'm saying, I want a GNU/Linux system. (Yes, it's not required, I can install MS-DOS, HURD, HP-UX or Android.) That means POSIX, LSB... That's what 99%+ of programs targeting GNU/Linux expect.
Do you have a source for this or is it FUD?
http://lists.freedesktop.org/archives/systemd-devel/2014-May...
