* `nix-store -qR' and friends: print the paths sorted topologically

  under the references relation.  This is useful for commands that
  want to copy paths to another Nix store in the right order.

1 files changed, 5 insertions, 0 deletions

diff --git a/src/libstore/store-api.hh b/src/libstore/store-api.hh
index 1f2d60f11c..8531eb0404 100644
--- a/src/libstore/store-api.hh
+++ b/src/libstore/store-api.hh
@@ -242,6 +242,11 @@ Path addPermRoot(const Path & storePath, const Path & gcRoot,
     bool indirect, bool allowOutsideRootsDir = false);
 
 
+/* Sort a set of paths topologically under the references relation.
+   If p refers to q, then p follows q in this list. */
+Paths topoSortPaths(const PathSet & paths);
+
+
 /* For now, there is a single global store API object, but we'll
    purify that in the future. */
 extern boost::shared_ptr<StoreAPI> store;