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100 Years of Macintosh
Zero seconds on the Mac OS system clock is January 1, 1904. The Mac OS epoch hits 100 years ... now. That's assuming you live in the Pacific time zone, anyway: the Mac OS epoch is unique in that it is time zone-specific. Of course, none of this applies unless you are running Mac OS, and all you Mac users are using Mac OS X, right? (Geek note: the Mac OS epoch is unsigned, which is why it can count over 100 years from 0 seconds, and 32-bit Unix can't, though it can count backward to 1901.)
The article confuses epoch and ticks. The epoch is a fixed point in time. Ticks is a number of seconds (or other time unit) since the epoch.
Since Apple models itself a hardware company, do they offer patches on a similar basis as Microsoft or to they rely more on the BSD patching system?
Closer to Microsoft than anything else. Apple's patches generally come in the form of installer applications that can be downloaded and installed automatically via the bundled "Software Update" application (GUI and command line) or can be downloaded and installed manually from the support section of their website.
Apple does not publish the source of any of their GUI applications or the GUI framework itself. It does however release the source to the rest of the OS under the name "Darwin". Patches and other updates to Mac OS X generally find their way into Darwin and can be browsed at http://developer.apple.com/darwin.
The typical artist/writer/mom-or-dad user can click a couple buttons and have OS X update itself (or even set it to always keep itself updated). More technical users can browse the Darwin website for more details. (This was recently done by several folks wanting to know more about how Panther, Mac OS X 10.3, does its automatic defragmentation and optimizing. They dug around in the Darwin souce until they found that particular part of the HFS+ architecture. Examined the code and made a few posts explaining the process to everyone else).
Actually it depends on the Mac - there are about 4 or 5 dates they can reset to:
1904, 1956, 1976 , 1984, 2001, depending on the machine.
This was a "Stump the Experts" Question at the 2003 world wide develoepr conference.
Some Macintosh models have clocks that reset to August 27, 1956 (and to a time other than midnight, I believe). This is the birthdate (and time) of Ray Montagne, the Apple engineer and programmer who designed the chip that controlled the PRAM on those models.
As for January 1, 1904, this date was selected because the original Mac's clock (which counts in seconds) can encompass a period of about 136 years. Selecting 1904 as the start date means that the 136-year period covered by the clock (1904-2040) includes the birthdate of nearly every Mac user, and extends well past the expected lifetime of the Mac OS. It also means that the simplest rule for leap-years can be used (every fourth year has an extra day), which simplifies day and date calculations. They didn't choose the year 1900 because it was not a leap year.
~Philly
Actually, in just three weeks there will be a real anniversary of the introduction of the Macintosh - January 24th, 1984.