[Nix-dev] path `xxx' is required, but there is no substituter that can build it

[Eelco Dolstra]

Hi,

Peter Simons wrote:

> nix-env has stopped working on my machine. No matter what package I try
> to install, the outcome is invariably this:
> 
>   $ nix-env -i -A swiProlog
>   installing `swi-prolog-5.6.51'
>   don't know how to build the following paths (may be caused by read-only store access):

The "may be caused by read-only store access" means that you don't have write
access to the Nix store.  Nix-env automatically goes into read-only mode if it
cannot open the file /nix/var/nix/db/big-lock (or whatever it is for your
prefix) for writing.  So you should check why that fails.

The error message could be nicer though.

-- 
Eelco Dolstra | http://www.st.ewi.tudelft.nl/~dolstra/