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On Sat, Sep 17, 2011 at 11:41 AM, Michael Mol <mikemol@×××××.com> wrote: |
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> On Sat, Sep 17, 2011 at 10:50 AM, Canek Peláez Valdés <caneko@×××××.com> wrote: |
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>> On Sat, Sep 17, 2011 at 2:45 AM, Joost Roeleveld <joost@××××××××.org> wrote: |
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> [[snippage]] |
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>>> I still think Gnome (or any other desktop environment) should not care about |
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>>> which init-system is being used. |
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>> |
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>> And they will not. They will only use some capabilities that a system |
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>> provides, and use it if available. It's the exact same thing as udev. |
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>> |
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> |
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> [[snippage]] |
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> |
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>> a) dbus is not part of the GUI, b) like it or not, it's the |
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>> standardized IPC mechanism in Linux. If it's available, let's use it. |
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> |
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> This is exactly the same attitude of convenience that led to udev |
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> being abused, and then to the very decisions by udev's maintainer that |
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> started off the firestorm on this list over the last couple weeks. The |
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> system is *bloating* at an incredible rate. |
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> |
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>> |
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>>> There are already well-tested and working mechanisms for communication where |
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>>> needed. |
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>> |
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>> I would like for you to be more specific about them. |
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> |
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> Sockets, be they UNIX domain sockets, IPv4 or IPv6. |
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[snip] |
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> Shared memory: |
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[snip] |
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> Pipes: |
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[snip] |
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Yeah, but then you need to design, implement and debug a protocol |
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communication: what part of the wire speaks first, what does it says, |
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what are the valid responses, etc. |
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And then, if other component wants to communicate, it has to learn |
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your little protocol. dbus standardize this. And it uses sockets, |
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shared memory and pipes as building blocks, I believe, |
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|
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> Not sure what others there are, but those have existed longer than |
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> I've been alive, and been standard since the early 1990s. |
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|
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They are standard in the sense that they are a low level communication |
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standard API. An IPC is *way* more than that; dbus is an IPC, because |
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then you have high level "objects" and "methods", no matter the |
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language of the two sides of the wire communicating, or even if the |
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objects live in the same computer or not. |
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|
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BTW, there *was* an standard that did everything dbus does: ORB, the |
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Object Request Broker. They tried to use that as IPC years ago, but is |
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so damn complicated to implement right they decided to better |
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implement a new standard. The standard is dbus. |
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> Progress is |
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> adding new functionality, not reimplementing existing functionality as |
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> new APIs on top of the existing functionality. |
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I think you are wrong if you believe that dbus is just "existing |
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functionality as new APIs on top of the existing functionality". dbus |
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is a complete IPC system. Neither sockets, shared memory nor pipes are |
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an IPC, because they lack a well defined protocol. You *can* do the |
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same you do with dbus if you only use sockets/sharedmem/pipes, but |
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then you need to do it over and over and over again. Is like the |
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difference between assembler and C: you *can* do the same with both, |
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but that does not mean that is actually a good idea to only use |
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assembler. |
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> That's little better |
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> than busywork for people who could be building something actually new. |
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dbus offers new functionality, like I said. |
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Regards. |
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-- |
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Canek Peláez Valdés |
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Posgrado en Ciencia e Ingeniería de la Computación |
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Universidad Nacional Autónoma de México |
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