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Ever hear of SSHFS? Or the infinitely slow Tramp?

A mkzftree manpage. The first section tells you all about what it is.

The ZF extension is part of RockRidge, meaning that it will only work on RockRidge-aware OSes (that additionally support the ZF extension). A google search makes it appear that FreeBSD, Linux can use this, and SCO and IRIX can at least use RR (and therefore possibly ZF). If your OS isn't in the list (and isn't windows, which made up their own filesystem) then hit google yourself.

You mean just like you don't have to on Linux, either? Thanks for re-affirming the fact that difficult application installation on Linux is a myth.

/usr/lib/xscreensaver/epicycle

The epicycle manpage also has a HISTORY section which explains a bit about the history of the idea. It says :-

The geometry of epicycles was perfected by Hipparchus of Rhodes at some time around 125 B.C., 185 years after the birth of Aristarchus of Samos, the inventor of the heliocentric universe model. Hipparchus applied epicycles to the Sun and the Moon. Ptolemy of Alexandria went on to apply them to what was then the known universe, at around 150 A.D. Copernicus went on to apply them to the heliocentric model at the beginning of the sixteenth century. Johannes Kepler discovered that the planets actually move in elliptical orbits in about 1602. The inverse-square law of gravity was suggested by Boulliau in 1645. Isaac Newton's Principia Mathematica was published in 1687, and proved that Kepler's laws derived from Newtonian gravitation.

Slashdot being what it is, I'm sure there are readers who have corrections to the above. If you do, please post them as followup or email them to me.

...since my GNOME fish died last night.

He's finally working on a way to port the BSOD over to Linux and OSX for us!
That's just plains silly. Don't you know italready runs on Linux?

There are several reasons why Linux does not have non-executable stacks yet...

One of them is that gcc and the kernel use trampolines. From the gcc docs:

A "trampoline" is a small piece of code that is created at run time when the address of a nested function is taken. It normally resides on the stack, in the stack frame of the containing function.

AFAIK, linux uses trampolines at least in these places:

• Gcc uses them for nested functions (not very common though, but glibc has quite a few of those).
• The linux kernel uses (used?) trampolines for signal delivery.

Both problems can be addressed (the openwall patches take care of the kernel trampolines), but it's not as easy as turning off the PROT_EXEC bits in the stack.

Also, a non-exec stack is not a silver bullet: it only makes exploiting buffer overflows somewhat harder. Check out this article from Solar Designer (the OpenWall patch author).

On top of the above:

• Multithreaded programs have more than one stack, and they're not necessarily contiguous.
• As Theo's mail says, the i386 arch (which is still the most common linux arch, despite its suckiness) has a very limited way of implementing PROT_READ && ! PROT_EXEC pages:

  The i386 is not capable of doing per-page execute permission. At most it is only capable of drawing a line through the address space, by limiting the code segment length (using the code segment register). So we can say, "from 0 to this point is executable" and "from that point on to the end of userland is not executable".

You may now understand why Linus has so far judged that a non-executable stack was more trouble than it was worth.

I already have the best Microsoft software on Linux...

Absolutely true: http://worstphotos.fifi.org/pix/pix-00039.jpg. Seen on WinNT 4.0.

If you use Linux with kernel 2.4 or above, you can mount a single partition multiple times - using the '--bind' parameter for mount (man mount) - this allows you to mount a subdirectory of an already mounted partition again. Combined with the BSD feature of translucent file systems, this would be a cool solution ;)