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diff --git a/doc/manual/src/command-ref/nix-store.md b/doc/manual/src/command-ref/nix-store.md index 4a9acb0f6..c7c5fdd2f 100644 --- a/doc/manual/src/command-ref/nix-store.md +++ b/doc/manual/src/command-ref/nix-store.md @@ -13,838 +13,35 @@ The command `nix-store` performs primitive operations on the Nix store. You generally do not need to run this command manually. -`nix-store` takes exactly one *operation* flag which indicates the -subcommand to be performed. These are documented below. - -# Common options - -This section lists the options that are common to all operations. These -options are allowed for every subcommand, though they may not always -have an effect. - - - <span id="opt-add-root">[`--add-root`](#opt-add-root)</span> *path* - - Causes the result of a realisation (`--realise` and - `--force-realise`) to be registered as a root of the garbage - collector. *path* will be created as a symlink to the resulting - store path. In addition, a uniquely named symlink to *path* will - be created in `/nix/var/nix/gcroots/auto/`. For instance, - - ```console - $ nix-store --add-root /home/eelco/bla/result -r ... - - $ ls -l /nix/var/nix/gcroots/auto - lrwxrwxrwx 1 ... 2005-03-13 21:10 dn54lcypm8f8... -> /home/eelco/bla/result - - $ ls -l /home/eelco/bla/result - lrwxrwxrwx 1 ... 2005-03-13 21:10 /home/eelco/bla/result -> /nix/store/1r11343n6qd4...-f-spot-0.0.10 - ``` - - Thus, when `/home/eelco/bla/result` is removed, the GC root in the - `auto` directory becomes a dangling symlink and will be ignored by - the collector. - - > **Warning** - > - > Note that it is not possible to move or rename GC roots, since - > the symlink in the `auto` directory will still point to the old - > location. - - If there are multiple results, then multiple symlinks will be - created by sequentially numbering symlinks beyond the first one - (e.g., `foo`, `foo-2`, `foo-3`, and so on). - - - <span id="opt-stdin">[`--stdin`](#opt-stdin)</span> - - Read *paths…* from the standard input. - Useful for chaining nix-store commands. - -# Operation `--realise` - -## Synopsis - -`nix-store` {`--realise` | `-r`} *paths…* [`--dry-run`] - -## Description - -The operation `--realise` essentially “builds” the specified store -paths. Realisation is a somewhat overloaded term: - - - If the store path is a *derivation*, realisation ensures that the - output paths of the derivation are [valid] (i.e., - the output path and its closure exist in the file system). This - can be done in several ways. First, it is possible that the - outputs are already valid, in which case we are done - immediately. Otherwise, there may be [substitutes] - that produce the outputs (e.g., by downloading them). Finally, the - outputs can be produced by running the build task described - by the derivation. - - - If the store path is not a derivation, realisation ensures that the - specified path is valid (i.e., it and its closure exist in the file - system). If the path is already valid, we are done immediately. - Otherwise, the path and any missing paths in its closure may be - produced through substitutes. If there are no (successful) - substitutes, realisation fails. - -[valid]: ../glossary.md#gloss-validity -[substitutes]: ../glossary.md#gloss-substitute - -The output path of each derivation is printed on standard output. (For -non-derivations argument, the argument itself is printed.) - -The following flags are available: - - - `--dry-run`\ - Print on standard error a description of what packages would be - built or downloaded, without actually performing the operation. - - - `--ignore-unknown`\ - If a non-derivation path does not have a substitute, then silently - ignore it. - - - `--check`\ - This option allows you to check whether a derivation is - deterministic. It rebuilds the specified derivation and checks - whether the result is bitwise-identical with the existing outputs, - printing an error if that’s not the case. The outputs of the - specified derivation must already exist. When used with `-K`, if an - output path is not identical to the corresponding output from the - previous build, the new output path is left in - `/nix/store/name.check.` - -Special exit codes: - - - `100`\ - Generic build failure, the builder process returned with a non-zero - exit code. - - - `101`\ - Build timeout, the build was aborted because it did not complete - within the specified `timeout`. - - - `102`\ - Hash mismatch, the build output was rejected because it does not - match the [`outputHash` attribute of the - derivation](../language/advanced-attributes.md). - - - `104`\ - Not deterministic, the build succeeded in check mode but the - resulting output is not binary reproducible. - -With the `--keep-going` flag it's possible for multiple failures to -occur, in this case the 1xx status codes are or combined using binary -or. - - 1100100 - ^^^^ - |||`- timeout - ||`-- output hash mismatch - |`--- build failure - `---- not deterministic - -## Examples - -This operation is typically used to build [store derivation]s produced by -[`nix-instantiate`](./nix-instantiate.md): - -[store derivation]: ../glossary.md#gloss-store-derivation - -```console -$ nix-store -r $(nix-instantiate ./test.nix) -/nix/store/31axcgrlbfsxzmfff1gyj1bf62hvkby2-aterm-2.3.1 -``` - -This is essentially what [`nix-build`](nix-build.md) does. - -To test whether a previously-built derivation is deterministic: - -```console -$ nix-build '<nixpkgs>' -A hello --check -K -``` - -Use [`--read-log`](#operation---read-log) to show the stderr and stdout of a build: - -```console -$ nix-store --read-log $(nix-instantiate ./test.nix) -``` - -# Operation `--serve` - -## Synopsis - -`nix-store` `--serve` [`--write`] - -## Description - -The operation `--serve` provides access to the Nix store over stdin and -stdout, and is intended to be used as a means of providing Nix store -access to a restricted ssh user. - -The following flags are available: - - - `--write`\ - Allow the connected client to request the realization of - derivations. In effect, this can be used to make the host act as a - remote builder. - -## Examples - -To turn a host into a build server, the `authorized_keys` file can be -used to provide build access to a given SSH public key: - -```console -$ cat <<EOF >>/root/.ssh/authorized_keys -command="nice -n20 nix-store --serve --write" ssh-rsa AAAAB3NzaC1yc2EAAAA... -EOF -``` - -# Operation `--gc` - -## Synopsis - -`nix-store` `--gc` [`--print-roots` | `--print-live` | `--print-dead`] [`--max-freed` *bytes*] - -## Description - -Without additional flags, the operation `--gc` performs a garbage -collection on the Nix store. That is, all paths in the Nix store not -reachable via file system references from a set of “roots”, are deleted. - -The following suboperations may be specified: - - - `--print-roots`\ - This operation prints on standard output the set of roots used by - the garbage collector. - - - `--print-live`\ - This operation prints on standard output the set of “live” store - paths, which are all the store paths reachable from the roots. Live - paths should never be deleted, since that would break consistency — - it would become possible that applications are installed that - reference things that are no longer present in the store. - - - `--print-dead`\ - This operation prints out on standard output the set of “dead” store - paths, which is just the opposite of the set of live paths: any path - in the store that is not live (with respect to the roots) is dead. - -By default, all unreachable paths are deleted. The following options -control what gets deleted and in what order: - - - `--max-freed` *bytes*\ - Keep deleting paths until at least *bytes* bytes have been deleted, - then stop. The argument *bytes* can be followed by the - multiplicative suffix `K`, `M`, `G` or `T`, denoting KiB, MiB, GiB - or TiB units. - -The behaviour of the collector is also influenced by the -`keep-outputs` and `keep-derivations` settings in the Nix -configuration file. - -By default, the collector prints the total number of freed bytes when it -finishes (or when it is interrupted). With `--print-dead`, it prints the -number of bytes that would be freed. - -## Examples - -To delete all unreachable paths, just do: - -```console -$ nix-store --gc -deleting `/nix/store/kq82idx6g0nyzsp2s14gfsc38npai7lf-cairo-1.0.4.tar.gz.drv' -... -8825586 bytes freed (8.42 MiB) -``` - -To delete at least 100 MiBs of unreachable paths: - -```console -$ nix-store --gc --max-freed $((100 * 1024 * 1024)) -``` - -# Operation `--delete` - -## Synopsis - -`nix-store` `--delete` [`--ignore-liveness`] *paths…* - -## Description - -The operation `--delete` deletes the store paths *paths* from the Nix -store, but only if it is safe to do so; that is, when the path is not -reachable from a root of the garbage collector. This means that you can -only delete paths that would also be deleted by `nix-store --gc`. Thus, -`--delete` is a more targeted version of `--gc`. - -With the option `--ignore-liveness`, reachability from the roots is -ignored. However, the path still won’t be deleted if there are other -paths in the store that refer to it (i.e., depend on it). - -## Example - -```console -$ nix-store --delete /nix/store/zq0h41l75vlb4z45kzgjjmsjxvcv1qk7-mesa-6.4 -0 bytes freed (0.00 MiB) -error: cannot delete path `/nix/store/zq0h41l75vlb4z45kzgjjmsjxvcv1qk7-mesa-6.4' since it is still alive -``` - -# Operation `--query` - -## Synopsis - -`nix-store` {`--query` | `-q`} - {`--outputs` | `--requisites` | `-R` | `--references` | - `--referrers` | `--referrers-closure` | `--deriver` | `-d` | - `--graph` | `--tree` | `--binding` *name* | `-b` *name* | `--hash` | - `--size` | `--roots`} - [`--use-output`] [`-u`] [`--force-realise`] [`-f`] - *paths…* - -## Description - -The operation `--query` displays information about [store path]s. -The queries are described below. At most one query can be -specified. The default query is `--outputs`. - -The paths *paths* may also be symlinks from outside of the Nix store, to -the Nix store. In that case, the query is applied to the target of the -symlink. - -## Common query options - - - `--use-output`; `-u`\ - For each argument to the query that is a [store derivation], apply the - query to the output path of the derivation instead. - - - `--force-realise`; `-f`\ - Realise each argument to the query first (see [`nix-store - --realise`](#operation---realise)). - -## Queries - - - `--outputs`\ - Prints out the [output path]s of the store - derivations *paths*. These are the paths that will be produced when - the derivation is built. - - - `--requisites`; `-R`\ - Prints out the [closure] of the given *paths*. - - This query has one option: - - - `--include-outputs` - Also include the existing output paths of [store derivation]s, - and their closures. - - This query can be used to implement various kinds of deployment. A - *source deployment* is obtained by distributing the closure of a - store derivation. A *binary deployment* is obtained by distributing - the closure of an output path. A *cache deployment* (combined - source/binary deployment, including binaries of build-time-only - dependencies) is obtained by distributing the closure of a store - derivation and specifying the option `--include-outputs`. - - - `--references`\ - Prints the set of [references]s of the store paths - *paths*, that is, their immediate dependencies. (For *all* - dependencies, use `--requisites`.) - - [reference]: ../glossary.md#gloss-reference - - - `--referrers`\ - Prints the set of *referrers* of the store paths *paths*, that is, - the store paths currently existing in the Nix store that refer to - one of *paths*. Note that contrary to the references, the set of - referrers is not constant; it can change as store paths are added or - removed. - - - `--referrers-closure`\ - Prints the closure of the set of store paths *paths* under the - referrers relation; that is, all store paths that directly or - indirectly refer to one of *paths*. These are all the path currently - in the Nix store that are dependent on *paths*. - - - `--deriver`; `-d`\ - Prints the [deriver] of the store paths *paths*. If - the path has no deriver (e.g., if it is a source file), or if the - deriver is not known (e.g., in the case of a binary-only - deployment), the string `unknown-deriver` is printed. - - [deriver]: ../glossary.md#gloss-deriver - - - `--graph`\ - Prints the references graph of the store paths *paths* in the format - of the `dot` tool of AT\&T's [Graphviz - package](http://www.graphviz.org/). This can be used to visualise - dependency graphs. To obtain a build-time dependency graph, apply - this to a store derivation. To obtain a runtime dependency graph, - apply it to an output path. - - - `--tree`\ - Prints the references graph of the store paths *paths* as a nested - ASCII tree. References are ordered by descending closure size; this - tends to flatten the tree, making it more readable. The query only - recurses into a store path when it is first encountered; this - prevents a blowup of the tree representation of the graph. - - - `--graphml`\ - Prints the references graph of the store paths *paths* in the - [GraphML](http://graphml.graphdrawing.org/) file format. This can be - used to visualise dependency graphs. To obtain a build-time - dependency graph, apply this to a [store derivation]. To obtain a - runtime dependency graph, apply it to an output path. - - - `--binding` *name*; `-b` *name*\ - Prints the value of the attribute *name* (i.e., environment - variable) of the [store derivation]s *paths*. It is an error for a - derivation to not have the specified attribute. - - - `--hash`\ - Prints the SHA-256 hash of the contents of the store paths *paths* - (that is, the hash of the output of `nix-store --dump` on the given - paths). Since the hash is stored in the Nix database, this is a fast - operation. - - - `--size`\ - Prints the size in bytes of the contents of the store paths *paths* - — to be precise, the size of the output of `nix-store --dump` on - the given paths. Note that the actual disk space required by the - store paths may be higher, especially on filesystems with large - cluster sizes. - - - `--roots`\ - Prints the garbage collector roots that point, directly or - indirectly, at the store paths *paths*. - -## Examples - -Print the closure (runtime dependencies) of the `svn` program in the -current user environment: - -```console -$ nix-store -qR $(which svn) -/nix/store/5mbglq5ldqld8sj57273aljwkfvj22mc-subversion-1.1.4 -/nix/store/9lz9yc6zgmc0vlqmn2ipcpkjlmbi51vv-glibc-2.3.4 -... -``` - -Print the build-time dependencies of `svn`: - -```console -$ nix-store -qR $(nix-store -qd $(which svn)) -/nix/store/02iizgn86m42q905rddvg4ja975bk2i4-grep-2.5.1.tar.bz2.drv -/nix/store/07a2bzxmzwz5hp58nf03pahrv2ygwgs3-gcc-wrapper.sh -/nix/store/0ma7c9wsbaxahwwl04gbw3fcd806ski4-glibc-2.3.4.drv -... lots of other paths ... -``` - -The difference with the previous example is that we ask the closure of -the derivation (`-qd`), not the closure of the output path that contains -`svn`. - -Show the build-time dependencies as a tree: - -```console -$ nix-store -q --tree $(nix-store -qd $(which svn)) -/nix/store/7i5082kfb6yjbqdbiwdhhza0am2xvh6c-subversion-1.1.4.drv -+---/nix/store/d8afh10z72n8l1cr5w42366abiblgn54-builder.sh -+---/nix/store/fmzxmpjx2lh849ph0l36snfj9zdibw67-bash-3.0.drv -| +---/nix/store/570hmhmx3v57605cqg9yfvvyh0nnb8k8-bash -| +---/nix/store/p3srsbd8dx44v2pg6nbnszab5mcwx03v-builder.sh -... -``` - -Show all paths that depend on the same OpenSSL library as `svn`: - -```console -$ nix-store -q --referrers $(nix-store -q --binding openssl $(nix-store -qd $(which svn))) -/nix/store/23ny9l9wixx21632y2wi4p585qhva1q8-sylpheed-1.0.0 -/nix/store/5mbglq5ldqld8sj57273aljwkfvj22mc-subversion-1.1.4 -/nix/store/dpmvp969yhdqs7lm2r1a3gng7pyq6vy4-subversion-1.1.3 -/nix/store/l51240xqsgg8a7yrbqdx1rfzyv6l26fx-lynx-2.8.5 -``` - -Show all paths that directly or indirectly depend on the Glibc (C -library) used by `svn`: - -```console -$ nix-store -q --referrers-closure $(ldd $(which svn) | grep /libc.so | awk '{print $3}') -/nix/store/034a6h4vpz9kds5r6kzb9lhh81mscw43-libgnomeprintui-2.8.2 -/nix/store/15l3yi0d45prm7a82pcrknxdh6nzmxza-gawk-3.1.4 -... -``` - -Note that `ldd` is a command that prints out the dynamic libraries used -by an ELF executable. - -Make a picture of the runtime dependency graph of the current user -environment: - -```console -$ nix-store -q --graph ~/.nix-profile | dot -Tps > graph.ps -$ gv graph.ps -``` - -Show every garbage collector root that points to a store path that -depends on `svn`: - -```console -$ nix-store -q --roots $(which svn) -/nix/var/nix/profiles/default-81-link -/nix/var/nix/profiles/default-82-link -/home/eelco/.local/state/nix/profiles/profile-97-link -``` - -# Operation `--add` - -## Synopsis - -`nix-store` `--add` *paths…* - -## Description - -The operation `--add` adds the specified paths to the Nix store. It -prints the resulting paths in the Nix store on standard output. - -## Example - -```console -$ nix-store --add ./foo.c -/nix/store/m7lrha58ph6rcnv109yzx1nk1cj7k7zf-foo.c -``` - -# Operation `--add-fixed` - -## Synopsis - -`nix-store` `--add-fixed` [`--recursive`] *algorithm* *paths…* - -## Description - -The operation `--add-fixed` adds the specified paths to the Nix store. -Unlike `--add` paths are registered using the specified hashing -algorithm, resulting in the same output path as a fixed-output -derivation. This can be used for sources that are not available from a -public url or broke since the download expression was written. - -This operation has the following options: - - - `--recursive`\ - Use recursive instead of flat hashing mode, used when adding - directories to the store. - -## Example - -```console -$ nix-store --add-fixed sha256 ./hello-2.10.tar.gz -/nix/store/3x7dwzq014bblazs7kq20p9hyzz0qh8g-hello-2.10.tar.gz -``` - -# Operation `--verify` - -## Synopsis - -`nix-store` `--verify` [`--check-contents`] [`--repair`] - -## Description - -The operation `--verify` verifies the internal consistency of the Nix -database, and the consistency between the Nix database and the Nix -store. Any inconsistencies encountered are automatically repaired. -Inconsistencies are generally the result of the Nix store or database -being modified by non-Nix tools, or of bugs in Nix itself. - -This operation has the following options: - - - `--check-contents`\ - Checks that the contents of every valid store path has not been - altered by computing a SHA-256 hash of the contents and comparing it - with the hash stored in the Nix database at build time. Paths that - have been modified are printed out. For large stores, - `--check-contents` is obviously quite slow. - - - `--repair`\ - If any valid path is missing from the store, or (if - `--check-contents` is given) the contents of a valid path has been - modified, then try to repair the path by redownloading it. See - `nix-store --repair-path` for details. - -# Operation `--verify-path` - -## Synopsis - -`nix-store` `--verify-path` *paths…* - -## Description - -The operation `--verify-path` compares the contents of the given store -paths to their cryptographic hashes stored in Nix’s database. For every -changed path, it prints a warning message. The exit status is 0 if no -path has changed, and 1 otherwise. - -## Example - -To verify the integrity of the `svn` command and all its dependencies: - -```console -$ nix-store --verify-path $(nix-store -qR $(which svn)) -``` - -# Operation `--repair-path` - -## Synopsis - -`nix-store` `--repair-path` *paths…* - -## Description - -The operation `--repair-path` attempts to “repair” the specified paths -by redownloading them using the available substituters. If no -substitutes are available, then repair is not possible. - -> **Warning** -> -> During repair, there is a very small time window during which the old -> path (if it exists) is moved out of the way and replaced with the new -> path. If repair is interrupted in between, then the system may be left -> in a broken state (e.g., if the path contains a critical system -> component like the GNU C Library). - -## Example - -```console -$ nix-store --verify-path /nix/store/dj7a81wsm1ijwwpkks3725661h3263p5-glibc-2.13 -path `/nix/store/dj7a81wsm1ijwwpkks3725661h3263p5-glibc-2.13' was modified! - expected hash `2db57715ae90b7e31ff1f2ecb8c12ec1cc43da920efcbe3b22763f36a1861588', - got `481c5aa5483ebc97c20457bb8bca24deea56550d3985cda0027f67fe54b808e4' - -$ nix-store --repair-path /nix/store/dj7a81wsm1ijwwpkks3725661h3263p5-glibc-2.13 -fetching path `/nix/store/d7a81wsm1ijwwpkks3725661h3263p5-glibc-2.13'... -… -``` - -# Operation `--dump` - -## Synopsis - -`nix-store` `--dump` *path* - -## Description - -The operation `--dump` produces a NAR (Nix ARchive) file containing the -contents of the file system tree rooted at *path*. The archive is -written to standard output. - -A NAR archive is like a TAR or Zip archive, but it contains only the -information that Nix considers important. For instance, timestamps are -elided because all files in the Nix store have their timestamp set to 1 -anyway. Likewise, all permissions are left out except for the execute -bit, because all files in the Nix store have 444 or 555 permission. - -Also, a NAR archive is *canonical*, meaning that “equal” paths always -produce the same NAR archive. For instance, directory entries are -always sorted so that the actual on-disk order doesn’t influence the -result. This means that the cryptographic hash of a NAR dump of a -path is usable as a fingerprint of the contents of the path. Indeed, -the hashes of store paths stored in Nix’s database (see `nix-store -q ---hash`) are SHA-256 hashes of the NAR dump of each store path. - -NAR archives support filenames of unlimited length and 64-bit file -sizes. They can contain regular files, directories, and symbolic links, -but not other types of files (such as device nodes). - -A Nix archive can be unpacked using `nix-store ---restore`. - -# Operation `--restore` - -## Synopsis - -`nix-store` `--restore` *path* - -## Description - -The operation `--restore` unpacks a NAR archive to *path*, which must -not already exist. The archive is read from standard input. - -# Operation `--export` - -## Synopsis - -`nix-store` `--export` *paths…* - -## Description - -The operation `--export` writes a serialisation of the specified store -paths to standard output in a format that can be imported into another -Nix store with `nix-store --import`. This is like `nix-store ---dump`, except that the NAR archive produced by that command doesn’t -contain the necessary meta-information to allow it to be imported into -another Nix store (namely, the set of references of the path). - -This command does not produce a *closure* of the specified paths, so if -a store path references other store paths that are missing in the target -Nix store, the import will fail. To copy a whole closure, do something -like: - -```console -$ nix-store --export $(nix-store -qR paths) > out -``` - -To import the whole closure again, run: - -```console -$ nix-store --import < out -``` - -# Operation `--import` - -## Synopsis - -`nix-store` `--import` - -## Description - -The operation `--import` reads a serialisation of a set of store paths -produced by `nix-store --export` from standard input and adds those -store paths to the Nix store. Paths that already exist in the Nix store -are ignored. If a path refers to another path that doesn’t exist in the -Nix store, the import fails. - -# Operation `--optimise` - -## Synopsis - -`nix-store` `--optimise` - -## Description - -The operation `--optimise` reduces Nix store disk space usage by finding -identical files in the store and hard-linking them to each other. It -typically reduces the size of the store by something like 25-35%. Only -regular files and symlinks are hard-linked in this manner. Files are -considered identical when they have the same NAR archive serialisation: -that is, regular files must have the same contents and permission -(executable or non-executable), and symlinks must have the same -contents. - -After completion, or when the command is interrupted, a report on the -achieved savings is printed on standard error. - -Use `-vv` or `-vvv` to get some progress indication. - -## Example - -```console -$ nix-store --optimise -hashing files in `/nix/store/qhqx7l2f1kmwihc9bnxs7rc159hsxnf3-gcc-4.1.1' -... -541838819 bytes (516.74 MiB) freed by hard-linking 54143 files; -there are 114486 files with equal contents out of 215894 files in total -``` - -# Operation `--read-log` - -## Synopsis - -`nix-store` {`--read-log` | `-l`} *paths…* - -## Description - -The operation `--read-log` prints the build log of the specified store -paths on standard output. The build log is whatever the builder of a -derivation wrote to standard output and standard error. If a store path -is not a derivation, the deriver of the store path is used. - -Build logs are kept in `/nix/var/log/nix/drvs`. However, there is no -guarantee that a build log is available for any particular store path. -For instance, if the path was downloaded as a pre-built binary through a -substitute, then the log is unavailable. - -## Example - -```console -$ nix-store -l $(which ktorrent) -building /nix/store/dhc73pvzpnzxhdgpimsd9sw39di66ph1-ktorrent-2.2.1 -unpacking sources -unpacking source archive /nix/store/p8n1jpqs27mgkjw07pb5269717nzf5f8-ktorrent-2.2.1.tar.gz -ktorrent-2.2.1/ -ktorrent-2.2.1/NEWS -... -``` - -# Operation `--dump-db` - -## Synopsis - -`nix-store` `--dump-db` [*paths…*] - -## Description - -The operation `--dump-db` writes a dump of the Nix database to standard -output. It can be loaded into an empty Nix store using `--load-db`. This -is useful for making backups and when migrating to different database -schemas. - -By default, `--dump-db` will dump the entire Nix database. When one or -more store paths is passed, only the subset of the Nix database for -those store paths is dumped. As with `--export`, the user is responsible -for passing all the store paths for a closure. See `--export` for an -example. - -# Operation `--load-db` - -## Synopsis - -`nix-store` `--load-db` - -## Description - -The operation `--load-db` reads a dump of the Nix database created by -`--dump-db` from standard input and loads it into the Nix database. - -# Operation `--print-env` - -## Synopsis - -`nix-store` `--print-env` *drvpath* - -## Description - -The operation `--print-env` prints out the environment of a derivation -in a format that can be evaluated by a shell. The command line arguments -of the builder are placed in the variable `_args`. - -## Example - -```console -$ nix-store --print-env $(nix-instantiate '<nixpkgs>' -A firefox) -… -export src; src='/nix/store/plpj7qrwcz94z2psh6fchsi7s8yihc7k-firefox-12.0.source.tar.bz2' -export stdenv; stdenv='/nix/store/7c8asx3yfrg5dg1gzhzyq2236zfgibnn-stdenv' -export system; system='x86_64-linux' -export _args; _args='-e /nix/store/9krlzvny65gdc8s7kpb6lkx8cd02c25c-default-builder.sh' -``` - -# Operation `--generate-binary-cache-key` - -## Synopsis - -`nix-store` `--generate-binary-cache-key` *key-name* *secret-key-file* *public-key-file* - -## Description - -This command generates an [Ed25519 key pair](http://ed25519.cr.yp.to/) -that can be used to create a signed binary cache. It takes three -mandatory parameters: - -1. A key name, such as `cache.example.org-1`, that is used to look up - keys on the client when it verifies signatures. It can be anything, - but it’s suggested to use the host name of your cache (e.g. - `cache.example.org`) with a suffix denoting the number of the key - (to be incremented every time you need to revoke a key). - -2. The file name where the secret key is to be stored. - -3. The file name where the public key is to be stored. +`nix-store` takes exactly one *operation* flag which indicates the subcommand to be performed. The following operations are available: + +- [`--realise`](./nix-store/realise.md) +- [`--serve`](./nix-store/serve.md) +- [`--gc`](./nix-store/gc.md) +- [`--delete`](./nix-store/delete.md) +- [`--query`](./nix-store/query.md) +- [`--add`](./nix-store/add.md) +- [`--add-fixed`](./nix-store/add-fixed.md) +- [`--verify`](./nix-store/verify.md) +- [`--verify-path`](./nix-store/verify-path.md) +- [`--repair-path`](./nix-store/repair-path.md) +- [`--dump`](./nix-store/dump.md) +- [`--restore`](./nix-store/restore.md) +- [`--export`](./nix-store/export.md) +- [`--import`](./nix-store/import.md) +- [`--optimise`](./nix-store/optimise.md) +- [`--read-log`](./nix-store/read-log.md) +- [`--dump-db`](./nix-store/dump-db.md) +- [`--load-db`](./nix-store/load-db.md) +- [`--print-env`](./nix-store/print-env.md) +- [`--generate-binary-cache-key`](./nix-store/generate-binary-cache-key.md) + +These pages can be viewed offline: + +- `man nix-store-<operation>`. + + Example: `man nix-store-realise` + +- `nix-store --help --<operation>` + + Example: `nix-store --help --realise` |