Hacker's Guide to Setting Up Your Mac

That''s quite witty! Do you also make all of your bread from the base ingredients too? :-)

It's always been prevelant everywhere.

The biggest one in Mac OS X history I remember is haxies:

http://en.wikipedia.org/wiki/Haxie

"Haxies are a source of controversy among Macintosh software developers. Because haxies make changes to Mac OS X that Apple did not intend, they complicate the operating environment for other developers' applications, and are frequently the cause of system instability and unexpected crashes.[1] Applications by Bare Bones software display a dialog after crashing (or are force quit by the user) if haxies are detected on the system. The Omni Group routinely asks users to remove Application Enhancer modules before contacting customer support for help with their applications.

According to a post by an Apple employee on an Apple mailing list, Apple ignores all crash reports submitted by users if they show that APE is installed."

http://daringfireball.net/2007/10/blue_in_the_face

"Reports abound regarding users suffering from a “blue screen” after upgrading to Leopard: they upgrade, reboot, and get stuck at a blank blue screen.

But, as far as I can tell, there is no mystery involved. There is one and only one known cause for this problem: old versions of Unsanity’s Application Enhancer, a.k.a. APE. Versions 2.0.2 and 2.0.3 of APE are apparently inert but harmless on Leopard. But at least some, if not all, versions of APE preceding version 2.0.2 are incompatible, and will render the system unbootable if left in place during an upgrade."

I disagree. / is where the stuff needed for single-user mode gets installed. /usr is where the OS's userland stuff gets installed. On Linux systems this includes everything that you get from your package manager, because this is considered to be part of your system. /usr/local is wher you install your own packages. For example, if I'm installing something from source, that's where I'm going to install it. Or if I'm building my own project, I would also install it there.

On a Mac, there is no system-blessed pacakage manager - the official packages are pre-installed on your Mac and only change when you get an OS update. They tend to be installed in /Library or ~/Library. All of the add-on package managers therefore play a role much closer to that of hand-installed source. It's logical that they install to /ur/local. In particular, one of my main use case for package managers is when I want to try out a package that has a whole bunch of dependencies. I might want to compile the package that interests me by hand, as I need to tweak the config, but I don't want to have to do the configure-make-make install dance for the 30 packages that it has as dependencies. That's where homebrew / MacPorts comes into the picture, they save me that work. But they should be installed into the same hierachy as the package that does interest me, as they are at the same level of "officialness".

One last thing. I know Fedora, Gentoo and MacOSX fairly well, and I have also worked a fair bit on a hand-rolled linux distribution. None of them ever had /usr/local/lib in their LD_LIBRARY_PATH by default, I've always had to configure that in my .bash_profile. This is exactly what you would expect, by default the directory should be empty, so why add it to the default LD_LIBRARY_PATH, that doesn't make any sense.

This is very true, and I too happily go to Linux land for servers. But for the typical target market of Apple devices (this is debatable), most people are happier with the download / open DMG / drag to applications scenario instead of typing, no?

You can enable it for the Terminal only.

As the other commenter stated, it's an X11 thing. Despite the prevalence of applications that run under X11 and the XQuartz availability, the native UI under OSX is Quartz which handles everything under OpenGL I believe....?