For several platforms we don't currently have "native" Nix packages
(e.g. Mac OS X and FreeBSD). This provides the next best thing: a
tarball containing the closure of Nix, plus a simple script
"nix-finish-install" that initialises the Nix database, registers the
paths in the closure as valid, and runs "nix-env -i /path/to/nix" to
initialise the user profile.
The tarball must be unpacked in the root directory. It creates
/nix/store/... and /usr/bin/nix-finish-install. Typical installation
is as follows:
$ cd /
$ tar xvf /path/to/nix-1.1pre1234_abcdef-x86_64-linux.tar.bz2
$ nix-finish-install
(if necessary add ~/.nix-profile/etc/profile.d/nix.sh to the shell
login scripts)
After this, /usr/bin/nix-finish-install can be deleted, if desired.
The downside to the binary tarball is that it's pretty big (~55 MiB
for x86_64-linux).
