43 lines
1.8 KiB
XML
43 lines
1.8 KiB
XML
<section xmlns="http://docbook.org/ns/docbook"
|
|
xmlns:xlink="http://www.w3.org/1999/xlink"
|
|
xmlns:xi="http://www.w3.org/2001/XInclude"
|
|
version="5.0"
|
|
xml:id="sec-collisions-nixenv">
|
|
|
|
<title>Collisions in <command>nix-env</command></title>
|
|
|
|
<para>Symptom: when installing or upgrading, you get an error message such as
|
|
|
|
<screen>
|
|
$ nix-env -i docbook-xml
|
|
...
|
|
adding /nix/store/s5hyxgm62gk2...-docbook-xml-4.2
|
|
collision between `/nix/store/s5hyxgm62gk2...-docbook-xml-4.2/xml/dtd/docbook/calstblx.dtd'
|
|
and `/nix/store/06h377hr4b33...-docbook-xml-4.3/xml/dtd/docbook/calstblx.dtd'
|
|
at /nix/store/...-builder.pl line 62.</screen>
|
|
|
|
</para>
|
|
|
|
<para>The cause is that two installed packages in the user environment
|
|
have overlapping filenames (e.g.,
|
|
<filename>xml/dtd/docbook/calstblx.dtd</filename>. This usually
|
|
happens when you accidentally try to install two versions of the same
|
|
package. For instance, in the example above, the Nix Packages
|
|
collection contains two versions of <literal>docbook-xml</literal>, so
|
|
<command>nix-env -i</command> will try to install both. The default
|
|
user environment builder has no way to way to resolve such conflicts,
|
|
so it just gives up.</para>
|
|
|
|
<para>Solution: remove one of the offending packages from the user
|
|
environment (if already installed) using <command>nix-env
|
|
-e</command>, or specify exactly which version should be installed
|
|
(e.g., <literal>nix-env -i docbook-xml-4.2</literal>).</para>
|
|
|
|
<para>Alternatively, you can modify the user environment builder
|
|
script (in
|
|
<filename><replaceable>prefix</replaceable>/share/nix/corepkgs/buildenv/builder.pl</filename>)
|
|
to implement some conflict resolution policy. E.g., the script could
|
|
be modified to rename conflicting file names, or to pick one over the
|
|
other.</para>
|
|
|
|
</section>
|