Warning: This program is experimental and its interface is subject to change.
Name
nix log
- show the build log of the specified packages or paths, if available
Synopsis
nix log
[option...] installable
Examples
-
Get the build log of GNU Hello:
# nix log nixpkgs#hello
-
Get the build log of a specific store path:
# nix log /nix/store/lmngj4wcm9rkv3w4dfhzhcyij3195hiq-thunderbird-52.2.1
-
Get a build log from a specific binary cache:
# nix log --store https://cache.nixos.org nixpkgs#hello
Description
This command prints the log of a previous build of the derivation installable on standard output.
Nix looks for build logs in two places:
-
In the directory
/nix/var/log/nix/drvs
, which contains logs for locally built derivations. -
In the binary caches listed in the
substituters
setting. Logs should be named<cache>/log/<base-name-of-store-path>
, wherestore-path
is a derivation, e.g.https://cache.nixos.org/log/dvmig8jgrdapvbyxb1rprckdmdqx08kv-hello-2.10.drv
. For non-derivation store paths, Nix will first try to determine the deriver by fetching the.narinfo
file for this store path.
Options
--debugger
start an interactive environment if evaluation fails
Common evaluation options:
-
--arg
name expr
Pass the value expr as the argument name to Nix functions. -
--argstr
name string
Pass the string string as the argument name to Nix functions. -
--eval-store
store-url
The Nix store to use for evaluations. -
--impure
Allow access to mutable paths and repositories. -
--include
/-I
path
Add path to the list of locations used to look up<...>
file names. -
--override-flake
original-ref resolved-ref
Override the flake registries, redirecting original-ref to resolved-ref.
Common flake-related options:
-
--commit-lock-file
Commit changes to the flake's lock file. -
--inputs-from
flake-url
Use the inputs of the specified flake as registry entries. -
--no-registries
Don't allow lookups in the flake registries. This option is deprecated; use--no-use-registries
. -
--no-update-lock-file
Do not allow any updates to the flake's lock file. -
--no-write-lock-file
Do not write the flake's newly generated lock file. -
--override-input
input-path flake-url
Override a specific flake input (e.g.dwarffs/nixpkgs
). This implies--no-write-lock-file
. -
--recreate-lock-file
Recreate the flake's lock file from scratch. -
--update-input
input-path
Update a specific flake input (ignoring its previous entry in the lock file).
Options that change the interpretation of installables:
-
--derivation
Operate on the store derivation rather than its outputs. -
--expr
expr
Interpret installables as attribute paths relative to the Nix expression expr. -
--file
/-f
file
Interpret installables as attribute paths relative to the Nix expression stored in file. If file is the character -, then a Nix expression will be read from standard input. Implies--impure
.