Why MAC OS X has UNIX Terminals

MAC OS X has UNIX terminals, we can use UNIX terminal to execute UNIX
commands, just like in UNIX environment. Why it that? MAC is one OS,
and UNIX is another OS. So it means MAC OS supports UNIX?
Please advise. thanks!!

 

Mac OS X is a real Unix system with Apple enhancements to provide the
Macintosh GUI (and underlying services that applications depend on).

 

Bah. I think you could make a strong case for MacOS being a real Unix
system, but not a real UNIX(r) system. Bugger the legalese of the Open
Group(tm).

 

I hope this is not a troll

Mac OS X takes the Carnage Mellon "Mach" micro-kernel, blends in the
"FreeBSD" UNIX POSIX and X/Open environment, and the Macintosh GUI to
create Mac OS X. Apple has even Open Sourced all the UNIX parts as
"Darwin" http://developer.apple.com/darwin/ but they keep the GUI
private as that is the part they make their Mac OS X money off from.

The UNIX under pinnings give Mac OS X its very solid "Industry Strength"
operating system. It allows Mac OS X to run Samba to allowing Macs to
mount Windows Shares and attach to Windows printers. It also allows
Macs to play nice in UNIX/Linux environments by doing things like
mounting NFS volumes. It allows Mac OS X to run the very popular and
very good Apache web server. It allows Mac OS X to be a router if you
want to use Mac OS X to share your internet connection.

The UNIX inside allows Mac OS X to run most of the popular Open Source
software available, and get the benefits for no extra efforts on the
part of Apple.

In fact being able to leverage off of the Open Source community, means
that Apple can quickly offer new features without needing to invest as
much in "Not Invented Here" software development.

So you also get a Terminal, and a bunch of UNIX commands. Well this
means that Mac OS X might attract UNIX and Linux users as it will allow
them to have a nice polished GUI _AND_ still have access to the UNIX
commands they know and love. And if they have to use with UNIX systems
at work, it makes is much easier for them.

These extra users help Apple in 2 ways. First, it is more customers
which increases Apple's market share. Second, many of these users are
also developers, and that increases the potential pool of developers
that might create the next killer App and it will be on a Mac first.
Win-Win situation.

The beauty of Mac OS X is that the vast majority of Mac users never
really need to know about the UNIX inside. Of course if you hang out in
these Mac news groups, some solutions are suggested as using Terminal
and UNIX commands, but that does not mean it is the only solution, it is
just a solution proposed by someone comfortable with using UNIX commands.

Bob Harris

PS. I am one of those day time UNIX users that just loves that Mac OS X
has UNIX inside.

 

Actually the entire MacOS API layer (Carbon and Cocoa) are kept
proprietary. This is more than just the GUI.

Correction, it /does/ attract UNIX and Linux users. I am one of them.

The main reason I bought my Mac three years ago was because of OS X.
At the time, the other system I was considering was a SunBlade 100
workstation.

I went with the Mac because I could get all of the Unix features I
wanted, plus the ability to run commercial Mac apps (which are far more
common and affordable than commercial Solaris apps.)

Ironically, three years later, I spend most of my time running the Mac
apps and very little time with the Unix apps.

-- David

 

Because it's a Good Idea.

 

Abstract: MacOS X is not in the spirit of UNIX.


Apple uses a Mach kernel with a "UNIX like" personality in a similar
way to NextStep. The main change from NextStep was to replace the
driver system from NextStep (which looks UNIX like) by a strange
new driver system (IoKit) that acts completely non orthogonal (*) and
is completely ignoring the spirit of UNIX. Note that NextSTep was
implementing the usual UNIX device interfaces.

MacOS X basically uses FreeBSD's libc and command line utilities.

Let me add some remarks on MacOS X:

- Like FreeBSD, MacOS X will never be able to get approved
for SUSv1 or SUSv2 compliance because the standard programming
interface includes basic system related types with
sizes > sifeof(long).

- POSIX does not like to mention the /dev/* interface for UNIX
(interestingly eough, POSIX mentions /dev/null) and for this
reason the strange IOKit interface does not really contradict
the POSIX standard.

- Due to recent changes in the FreeBSD interfaces, Macos x may be
able to become POSIX.1-2001 aproved in the future.


Note that Apple never did aproach the OpenGroup for a compliance test
and for this reason illegally claims that MacOS X is UNIX even before the
FreeBSD interfaces started to move towards to POSIX.1-2001



*) Although there is something like /dev/rdisk*, you cannot
send the usual IOCTLs to devices in the usual way.
For SCSI Generic you need e.g. to use strange non UNIX-like
calls to get handles for the ioctl() that you feed wit
something like "IOCompactDiscServices/0". Even this non
UNIX like system is completely non-orthogonal. Apple hides
e.g. CD-ROM drivers from this interface while it allows you
to send SCSI commands to CD-Writers. For unknown reason,
(although CD-ROM drives are _exactly_ the same as DVD-ROM
drives from programmers view) you need to use "IODVDServices"
for DVD drives......

 

MacOS X does not meet either of your points:

1) It has not been validated by the Open Group and in former
times would not have been able to meet the requirements.
The reason is that both Mac OS X and POSIX did move latetly.

2) Mac OS X is not even constructed like a historical UNIX
system.

3) Mac OS X has important deviations from those UNIX interfaces
that did not yet make it into POSIX or will probably never make
it into POSIX.

While MacOS X seems to work like UNIX for unexperienced users
it does not do so for programmers and experienced users.

 

I don't understand how the concept of orthogonality, or lack thereof,
applies to a description of programming interfaces.

 

Among the most useful ar chmod and chown - the counterparts in Finders
Get Info window are quite crippled (to say the least) unless you operate
on folders that were your omw to start with.

Also It's so easy for developers of e.g. open source utilities to port
them from linux/unix and put a Cocoa shell around the commands to make
really useful tools like ffmpeg and VCDgear easy to use.

 

Ah, a troll. MacOS X is a unix, yes.

 

this has become silly, along the lines of

it's a floorwax!
no! it's a desert topping!
floorwax!
desert topping!
stop it you two...it's both!

 

"Desert" topping???? What, like sagebrush? )

 

Then perhaps you haven't looked very hard. From the side bar
at <http://www.apple.com/macosx>, until the heading "Solid as
a rock":

"Panther improves the open-standard, industrial-strength,
UNIX-based foundation and now includes X11 for Mac OS X.
Along with an enhanced Terminal and updated open source
projects such as Python, FreeBSD 5 commands and libraries
make Mac OS X Panther the ultimate UNIX platform."

The first sentence indicates that Panther has a "UNIX-based
foundation". The second sentence indicates that certain
features make Panther "the ultimate UNIX platform".

So, it hinges on whether a "platform" is a "system", and
that's a semantic discussion that I won't participate in.

Beverly

 

You could run OSXvnc on the Mac and a suitable VNC client on your
OpenBSD system (does TightVNC run on OpenBSD?). OSXvnc will show the
full Mac display and control any Mac app running, not just the X11
environment.

And if you run a VNC server on your OpenBSD system, you can run "Chicken
of the VNC" on your Mac and conttrol your OpenBSD system.

Bob Harris

 

Works great with Solaris, too.

 

I don't really care about the legal right to use the term. As a user, I
go by the "if it looks like a duck and quacks like a duck" rule.

 

I should be very careful in making that claim about Cygwin, if I were
you. Cygwin explicitly _not_ claim to provde a "UNIX platform" for
Windows.

It does claim to be "a Linux-like environment for Windows, consisting
of a DLL which acts as a Linux API emulation layer providing substantial
Linux API functionality, and a a collection of tools, which provide
Linux look and feel" (quoted from <http://www.cygwin.com>)

Beverly

 

What an incredibly obtuse argument! Let me summarize, Apple on their
website claims Panther to be "the ultimate UNIX platform". In response
you said:
a) platform != system (which may or may not be true)
b) that Cygwin claims to be a UNIX platform for Windows.

I simply pointed out that Cygwin makes _no_ such claim, and you shouldn't
make that claim for them, as they go to length to distance themselves
from any such claim (second para, <http://www.cygwin.com>)

What matters (semantic or otherwise) is not what definition _you_ choose
to apply - what matters are the claims directly made by a vendor (Apple)
or a community (Cygwin).

 

Take a look at the Unix family tree, above. OS X is based on code which
can trace its ancestry directly back to the original UNIX system. Its
architecture is obviously different, but being a Unix has never really
been about internal kernel architecture.[/QUOTE]

Mac OS has no connection to UNIX history except for using BSD libc and
the commands. If your UNIX history chart believes something different,
throw it away.

For simple programs you are right, for more sophisticated programs
like cdrecord you are completely wrong.