Um, no. Mach is a micro-kernel, BSD uses a monolithic kernel, they aren't at all related even though Mach was originally intended to replace the BSD kernel (which never happened). Mach is in fact entirely platform agnostic (Windows NT's kernel is in fact based on a Mach-inspired hybrid kernel). Apple (NeXT Inc really, as this predates Apple's acquisition by a decade or so) implemented a BSD kernel emulator on top of Mach to allow for a BSD userspace to run beside the NeXTSTEP GUI which OS X's GUI evolved from.
Mach is very platform-agnostic, it doesn't proved full kernel services, just the core of a kernel, so you need a second layer on top of it to provide the API for drivers and userland. -Adam On Wed, Jul 16, 2008 at 11:17 AM, P. J. Alling <[EMAIL PROTECTED]> wrote: > I don't want to say Adam is wrong, so I won't, maybe they've found ways > around that. However the MACH Kernel is based on BSD Unix, it's not > like it's an entirely different animal. > > Adam Maas wrote: >> Actually, it's a descendant of NeXTSTEP with one single cosmetic >> feature of the old Mac OS (the menu bar) added and a bunch of UNIX >> userland grafted on the side. It really doesn't run on top of UNIX at >> all, the GUI runs directly on top of the MACH-based kernel, and uses a >> different set of API's than the Unix userland which runs beside it, >> nor does it particularly resemble the classic Mac OS. The only real >> Unixism that the GUI subscribes to is the filesystem, which it >> interacts with via some Unix API's. >> >> Oh, and root permissions to the filesystem are granted via sudo, OS X >> always asks for them, it never decides on its own to grant a user root >> permissions (which btw is rarely needed apart from doing system >> maintenance or installing drivers, unlike in Windows which typically >> requires Admin priviledges to install software). >> >> -Adam >> >> On Wed, Jul 16, 2008 at 9:36 AM, P. J. Alling <[EMAIL PROTECTED]> wrote: >> >>> Then this will be even more confusing. The current MAC OS is a >>> graphical user interface that resembles the original MAC OS built on a >>> version of UNIX. To do a lot of useful things you have to have root >>> privileges, (i.e. permission to do everything). However giving that >>> kind of permission is a recipe for disaster, as well as very bad from a >>> security standpoint. To make the user experience a bit less tiresome >>> and more seamless the MAC OS makes assumptions about when to grant these >>> privileges and when to revoke them. Sometimes it's just wrong. The >>> result can be mysterious and or annoying messages. >>> >>> David J Brooks wrote: >>> >>>> On Wed, Jul 16, 2008 at 9:06 AM, P. J. Alling <[EMAIL PROTECTED]> wrote: >>>> >>>> >>>>> I like to think that the unexplained happens when you build a GUI for >>>>> everyman on top of UNIX. This appears to be proof... >>>>> >>>>> >>>> You've lost me already. >>>> >>>> Dave >>>> >>>> >>>>> David J Brooks wrote: >>>>> >>>>> >>>>>> Monday i noticed i had "lost" about 5 gig of space, and i decided to >>>>>> trash the trash. >>>>>> >>>>>> That seemed to bring it back the last time. >>>>>> >>>>>> Now, every time i log on to the computer, i get a pop up screen >>>>>> saying" You do not have permission to delete file-"about your >>>>>> idisk.rtf." >>>>>> >>>>>> Also the same day, i had a screen pop up to say i needed more space >>>>>> added for my idisk. >>>>>> >>>>>> Could this be were my 5 gig went and why i am getting this new message.?? >>>>>> >>>>>> No big deal, i just close the pop up screen, more just curious. >>>>>> >>>>>> Dave >>>>>> >>>>>> >>>>>> >>>>>> >>>>> -- >>>>> You get further with a kind word and a gun, than with a kind word alone. >>>>> --Al Capone. >>>>> >>>>> >>>>> -- >>>>> PDML Pentax-Discuss Mail List >>>>> [email protected] >>>>> http://pdml.net/mailman/listinfo/pdml_pdml.net >>>>> to UNSUBSCRIBE from the PDML, please visit the link directly above and >>>>> follow the directions. >>>>> >>>>> >>>>> >>>> >>>> >>>> >>> -- >>> You get further with a kind word and a gun, than with a kind word alone. >>> --Al Capone. >>> >>> >>> -- >>> PDML Pentax-Discuss Mail List >>> [email protected] >>> http://pdml.net/mailman/listinfo/pdml_pdml.net >>> to UNSUBSCRIBE from the PDML, please visit the link directly above and >>> follow the directions. >>> >>> >> >> >> >> > > > -- > You get further with a kind word and a gun, than with a kind word alone. > --Al Capone. > > > -- > PDML Pentax-Discuss Mail List > [email protected] > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and follow > the directions. > -- M. Adam Maas http://www.mawz.ca Explorations of the City Around Us. -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
