All right,<div><br></div><div>Thanks a lot, that clarifies everything!!</div><div><br></div><div>I read that Ubuntu 10.04 will ship without HAL. I was not completely shure why udev+dbus was better. Now I see.</div><div><br> </div><div><br></div><div>Regards.</div><div><br></div><div>---Noe Nieto</div><div><br></div><div><br><br><div class="gmail_quote">2010/4/25 Lennart Poettering <span dir="ltr"><<a href="mailto:mzqohf@0pointer.de">mzqohf@0pointer.de</a>></span><br> <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;"><div><div></div><div class="h5">On Sun, 25.04.10 19:49, Noe Misael (<a href="mailto:tzicatl@gmail.com">tzicatl@gmail.com</a>) wrote:<br> <br> > Hi.<br> ><br> > I'm trying to understand how modern linux systems handle hardware devices. I<br> > have a general idea about how kernel drivers works and also have a general<br> > idea about how udev is a layer between the kernel and user-space.<br> ><br> > But when looking at HAL and Dbus, DeviceKit, Network Manager I started to<br> > get confused.<br> ><br> > Can anyone be so kind to explain me how are these software components<br> > interacting with each other?<br> <br> </div></div>Ignore devicekit. I doesn't exist, it never really came to be.<br> <br> Ignore HAL, too, as it is obsolete and only used by legacy code.<br> <br> udev provides low-level access to the linux device tree. Allows programs<br> to enumerate devices and their properties and get notifications when<br> devices come and go.<br> <br> dbus is a framework to allow programs to communicate with each other,<br> securely, reliably, and with a high-level object-oriented programming<br> interface.<br> <br> udisks (formerly known as DeviceKit-disks) is a daemon that sits on top<br> of libudev and other kernel interfaces and provides a high-level<br> interface to storage devices and is accessible via dbus to applications.<br> <br> upower (formerly known as DeviceKit-power) is a daemon that sits on top<br> of libudev and other kernel interfaces and provides a high-level<br> interface to power management and is accessible via dbus to apps.<br> <br> NetworkManager is a daemon that sits on top of libudev and other kernel<br> interfaces (and a couple of other daemons) and provides a high-level<br> interface to network configuration and setup and is accessible via dbus<br> to apps.<br> <br> (hal was a lot of this all mingled in one big daemon, and eventually<br> proved to suck in its design)<br> <br> Of course, NM should probably be renamed to "unetwork", and dbus to<br> "ubus". And PulseAudio to "usound", and X11 to "udisplay", and then<br> undescribable happiness would come down to all people of this world.<br> <br> Lennart<br> <font color="#888888"><br> --<br> Lennart Poettering Red Hat, Inc.<br> lennart [at] poettering [dot] net<br> <a href="http://0pointer.net/lennart/" target="_blank">http://0pointer.net/lennart/</a> GnuPG 0x1A015CC4<br> </font></blockquote></div><br></div>