A Technical History of Apple's Operating Systems - Mac OS X Internals

Mac OS X Internals (www.osxbook.com) 61
1.4.2. What Color is Your System?
In March 1988, after the Macintosh had been around for four years, some Apple
engineers and managers had an off-site meeting. As they brainstormed to come up
with future operating system strategies, they noted down their ideas on three sets of
index cards that were colored blue, pink, and red.
Blue would be the project for improving the existing Macintosh operating sys-
tem. It would eventually form the core of System 7.
Pink would soon become a revolutionary operating system project at Apple.
The operating system was planned to be object-oriented. It would have full memory
protection, multitasking with lightweight threads, a large number of protected ad-
dress spaces, and several other modern features. After languishing for many years at
Apple, Pink would move out to Taligent, a company jointly run by Apple and IBM.
We will briefly discuss Taligent in Section 1.6.4.
Since the color red is “pinker than pink,” ideas considered too advanced even
for Pink were made part of the Red project.
As the 1980s were drawing to an end, the system software was at major ver-
sion 6. System 7, a result of the Blue project, would be Apple’s most significant
system yet, both relatively and absolutely. However, that would not be until 1991.
Apple would come out with two interesting operating systems before that: GS/OS
and A/UX.
Gestalt
In 1989, Apple introduced a system call named “Gestalt” in version 6.0.4 of the
operating system. Gestalt allowed applications to dynamically query the capabilities
that were present in a running system configuration. It would go on to become a widely
used system call, and continues to exist in Mac OS X as a Carbon function.