I’m wondering if any of the Wizards here know anything definitive about the current Mac OS’s… I know they are derived from Linux, but most Linux software has to be recompiled to run on a Mac. Also, on a Mac, you don’t have the choice of KDE3, KDE4, Gnome, etc., that you do on Linux. Lastly, is Mac virtualization anything related to Xen, VMWare, etc.?
Thanks!
Patti
I’ll tell you what I know which isn’t much.
For sure, don’t be fooled it’s still ‘Evil Empire’ and ‘Vendor Lock In’. Undoubtedly good and far superior to M$, but also very pricey. There are some Purist MAC folk in the forum who may respond.
Apple uses BSD Unix which is an older cousin of Linux; so it is relatively easy to recompile programs to run on both Linux and BSD Unix.
Mac OS X is based loosely on BSD with the Mach kernel with a proprietary graphical environment built on top of it.
Porting Linux software is relatively trivial except for larger projects which use GNOME or QT libraries. You can use the X11+XCode environment that Apple offers to make porting software easier or use the Darwinports / MacPorts / DarwinForge to directly ‘evolve’ software for it that others have packaged, much like you would with SuSE or Ubuntu.
I’m not quite sure what you’re referring to with Mac virtualization?
On Sat, 25 Jul 2009 16:26:02 +0000, PattiMichelle wrote:
> the current Mac OS’s… I know they are derived from Linux,
They’re not. As others said, MacOSX is a derivative of BSD, not
Linux. 
Jim
On Sat, 2009-07-25 at 17:36 +0000, john hudson wrote:
> Apple uses BSD Unix which is an older cousin of Linux; so it is
> relatively easy to recompile programs to run on both Linux and BSD Unix.
>
>
BSD is the brother of Unix, not a cousin of Linux or of a Linux distro
really.
BSD and System V are the two primary branches of Unix (proper).
Linux is it’s own thing… was more inspired by fooling around with
Minix in fact, but even so, it stands alone (though I think Microsoft
wants everyone to believe it stole technology from them… which is
pretty humorous actually).
Linux does try to be very *ix like though. But that’s not necessarily a
requirement… and so Linux actually does many things better than Unix.
With that said Linux has a lot of POSIX-ishness about it… which makes
it somewhat similar to System V. However, BSD (which was in legal
turmoil at the time) was the hopeful contender for affordable Unix, and
so you see some BSD-ishness in Linux (especially early on).
BSD in general is different enough from System V to make some things
difficult (porting required). You could argue that has become better
since System V HAD to adopt certain BSD features (e.g. sockets, rpc’s)
in order to be practical.
So… it is very true that in some cases programs from BSD are NOT going
to compile well on a Linux based distro. YMMV.
It’s really best to say that System V and BSD are very GNU/Linux LIKE
things.
Thank you very much, everyone. I was a woeful WIndows user - woeful because I couldn’t “figure out” Linux. (I have 15 or so computers in my laboratory at work.) Then I discovered “Lindows” and haven’t looked back. After a few years, I settled on openSuSE (back during 10.0) to get away from having “corporate-controlled OS” at home. Luckily, there were great openSuSE forums and someone actually asked me to begin building packages for his repo. I especially love “back in the day” stories because I had a coworker who was doing Cromix (anyone remember that?) back before PC’s came out.
Though I don’t do any Linux development, it just feels better knowing what’s really going on - I guess being a laboratory/techie type makes knowing these things feel good - so thanks for the info. I just got through setting up tightVNC/FileZilla in an SSH tunnel (from a windows machine) so that one of the other scientists at work can use my 32-processor TYAN openSuSE box (also at work) for calculations. The only way I could have done that was to be part of the openSuSE community.
rotfl!Patti:P
PS: Now if I could only figure out how to get my lab hardware ported to Linux! One of the problems is, of course, drivers for A/D cards, etc. National Instruments is supporting Linux, but I have to admit, I think it would be a huge leap to jump at the same time to linux, port the drivers, and switch from VisualBasic to - what? Gambas? RealBASIC? …?
Just a footnote: Because Mac OS/X is derived from BSD, and BSD and Linux both aspire to POSIXness, command line programs can readily be made portable between the two environments. For C/C++ programs usually it amounts to some #ifdefs and perhaps some OS adaptation modules. For higher level languages, it’s even easier, e.g. a Perl/Python/Ruby/PHP program will probably just run unchanged, as the language implementors have done the hard part for you in porting to the OS environment. Ditto for Java, though some people would not call Java high-level.
However OS/X windowing is not X Windowing; it is a different system (Aqua? Cocoa? Carbon? see here: Mac OS X System Architecture). So GUI programs written for X will not work as-is on Macs. You can run an X server on a Mac, but it would be separate from the main windowing system. There are probably cross-platform GUI kits but I couldn’t name any off the top of my head.
Later: just did a search, there are Qt and GTK+ for OS/X. But GUIs are more than just the app and the toolkit, there are a lot of auxiliary services that have to be running. So cross-platform GUI programs could be messy. But obviously programs like Opera have solved this in their own way.
Thank goodness for that 
The current Xorg mess is enough to give anyone a headache.
Apple does have the enviable position of controlling the hardware platform on which OS/X runs. That’s one reason why they fight Hackintosh builders, the possible problems caused to the user experience might bring Apple products into disrepute. Not to mention the very profitable markup.
True, that is an advantage! (for macs) - makes their lives easy - the Open Source folks are working very hard (and succeeding for the largest part) to run on my pavilion as well as my home-built desktop. In fact, every computer I’ve ever installed on - even ones that Knoppix wouldnt’ boot upon. Shoot! They even can use windows drivers encased in a wrapper! And I can install Windows2003Enterprise Server x86_64 under Xen (on OpenSuSE 11.0) and get a completely virtual 8CPU server. All those technological feats make the Shuttle look low-tech.