From 8901acc97664aa8ebf687ee904428aa57a5192be Mon Sep 17 00:00:00 2001 From: Mikey Ariel Date: Wed, 27 Aug 2014 18:41:09 +0200 Subject: Restructuring the Nix manual --- doc/manual/glossary/glossary.xml | 179 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 179 insertions(+) create mode 100644 doc/manual/glossary/glossary.xml (limited to 'doc/manual/glossary/glossary.xml') diff --git a/doc/manual/glossary/glossary.xml b/doc/manual/glossary/glossary.xml new file mode 100644 index 000000000000..d74940c90b30 --- /dev/null +++ b/doc/manual/glossary/glossary.xml @@ -0,0 +1,179 @@ + + +Glossary + + + + + +derivation + + A description of a build action. The result of a + derivation is a store object. Derivations are typically specified + in Nix expressions using the derivation + primitive. These are translated into low-level + store derivations (implicitly by + nix-env and nix-build, or + explicitly by nix-instantiate). + + + + +store + + The location in the file system where store objects + live. Typically /nix/store. + + + + +store path + + The location in the file system of a store object, + i.e., an immediate child of the Nix store + directory. + + + + +store object + + A file that is an immediate child of the Nix store + directory. These can be regular files, but also entire directory + trees. Store objects can be sources (objects copied from outside of + the store), derivation outputs (objects produced by running a build + action), or derivations (files describing a build + action). + + + + +substitute + + A substitute is a command invocation stored in the + Nix database that describes how to build a store object, bypassing + normal the build mechanism (i.e., derivations). Typically, the + substitute builds the store object by downloading a pre-built + version of the store object from some server. + + + + +purity + + The assumption that equal Nix derivations when run + always produce the same output. This cannot be guaranteed in + general (e.g., a builder can rely on external inputs such as the + network or the system time) but the Nix model assumes + it. + + + + +Nix expression + + A high-level description of software packages and + compositions thereof. Deploying software using Nix entails writing + Nix expressions for your packages. Nix expressions are translated + to derivations that are stored in the Nix store. These derivations + can then be built. + + + + +reference + + A store path P is said to have a + reference to a store path Q if the store object + at P contains the path Q + somewhere. This implies than an execution involving + P potentially needs Q to be + present. The references of a store path are + the set of store paths to which it has a reference. + + + + +closure + + The closure of a store path is the set of store + paths that are directly or indirectly “reachable” from that store + path; that is, it’s the closure of the path under the references relation. For instance, + if the store object at path P contains a + reference to path Q, then Q is + in the closure of P. For correct deployment it + is necessary to deploy whole closures, since otherwise at runtime + files could be missing. The command nix-store + -qR prints out closures of store paths. + + + + +output path + + A store path produced by a derivation. + + + + +deriver + + The deriver of an output path is the store + derivation that built it. + + + + +validity + + A store path is considered + valid if it exists in the file system, is + listed in the Nix database as being valid, and if all paths in its + closure are also valid. + + + + +user environment + + An automatically generated store object that + consists of a set of symlinks to “active” applications, i.e., other + store paths. These are generated automatically by nix-env. See . + + + + + + +profile + + A symlink to the current user environment of a user, e.g., + /nix/var/nix/profiles/default. + + + + +NAR + + A Nix + ARchive. This is a serialisation of a path in + the Nix store. It can contain regular files, directories and + symbolic links. NARs are generated and unpacked using + nix-store --dump and nix-store + --restore. + + + + + + + + + -- cgit 1.4.1