[Nix-dev] transition to pure system

[Lluís Batlle i Rossell]

On Wed, Jan 05, 2011 at 10:05:17AM +0100, Florian Friesdorf wrote:
> On Tue, Jan 04, 2011 at 04:39:23PM -0700, Kevin Quick wrote:
> > On Tue, 04 Jan 2011 14:10:15 -0700, <7c6f434c at mail.ru> wrote:
> > 
> > >export LD_LIBRARY_PATH="$LD_LIBRARY_PATH:/var/run/current-system/sw/lib"
> > >export NIX_LDFLAGS="$NIX_LDFLAGS -L /var/run/current-system/sw/lib"
> > >export NIX_CFLAGS_COMPILE="$NIX_CFLAGS_COMPILE -I /var/run/current-system/sw/include"
> > >export PKG_CONFIG_PATH="$PKG_CONFIG_PATH:/var/run/current-system/sw/lib/pkgconfig"
> > 
> > Can someone explain the specific difference between
> > /var/run/current-system/sw/X and $HOME/.nix-profile/X paths?
> 
> The former is the active system profile, the latter your user's active
> user profile. A profile is fully self-contained and does not depend on
> other profiles.
The former is generated at "nixos-rebuild", evaluating nixos+nixpkgs at that
time.

The later is built accumilatively, through "nix-env -i" kind of operations,
where the evaluations of the members of the profile (the list of programs) is
done independently at the "nix-env -i" operation that brought the program in the
profile.

Both former and latter are built differently, with different degrees of freedom,
so different advantages and disadvantages.