null bytes in file names?

[Dominik Vogt <dominik.vogt@gmx.de>]

As far as I know, UNIX file systems allow null bytes in file
names.  Out of curiosity I tried generating such a file.  I edited
a file fn in a hex editor and put a single null byte into it.

Take I (with "touch"):

  $ touch $(< fn)
  touch: creating `': No such file or directory
  touch: creating `': No such file or directory
  $ touch $(< fn)
  touch: creating `': No such file or directory
  $ touch s$(< fn)t
  $ touch u"$(< fn)"v
  $ ls
  fn s t u

"u" might actually be named "u^@v" but displayed incorrectly by ls,
so let's try to access a file named "u".

  $ ls u
  u

Nope, the name got cut off.

  $ rm s t y

Take II (shell builtins only):

  $ echo foo > $(< fn)
  zsh: no such file or directory: 
  $ echo foo > "$(< fn)"
  zsh: no such file or directory: ^@
  $ echo foo > w$(< fn)x
  $ echo foo > y$(< fn)z
  $ ls
  fn w  x  y  z
  $ ls w y
  w  y

So, no luck.  I wonder where the problem comes from:

 - zsh? (4.0.4)
 - libc?
 - kernel? (linux-2.4.20)

Bye

Dominik ^_^  ^_^