Merge pull request #8532 from fricklerhandwerk/nix.conf-sections

split nix.conf man page into sections
This commit is contained in:
Valentin Gagarin 2023-06-20 13:16:14 +02:00 committed by GitHub
commit 3c618c43c6
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23

View file

@ -4,49 +4,67 @@
# Description # Description
By default Nix reads settings from the following places: Nix supports a variety of configuration settings, which are read from configuration files or taken as command line flags.
- The system-wide configuration file `sysconfdir/nix/nix.conf` (i.e. ## Configuration file
`/etc/nix/nix.conf` on most systems), or `$NIX_CONF_DIR/nix.conf` if
`NIX_CONF_DIR` is set. Values loaded in this file are not forwarded
to the Nix daemon. The client assumes that the daemon has already
loaded them.
- If `NIX_USER_CONF_FILES` is set, then each path separated by `:` By default Nix reads settings from the following places, in that order:
will be loaded in reverse order.
Otherwise it will look for `nix/nix.conf` files in `XDG_CONFIG_DIRS` 1. The system-wide configuration file `sysconfdir/nix/nix.conf` (i.e. `/etc/nix/nix.conf` on most systems), or `$NIX_CONF_DIR/nix.conf` if [`NIX_CONF_DIR`](./env-common.md#env-NIX_CONF_DIR) is set.
and `XDG_CONFIG_HOME`. If unset, `XDG_CONFIG_DIRS` defaults to
`/etc/xdg`, and `XDG_CONFIG_HOME` defaults to `$HOME/.config`
as per [XDG Base Directory Specification](https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html).
- If `NIX_CONFIG` is set, its contents is treated as the contents of Values loaded in this file are not forwarded to the Nix daemon.
a configuration file. The client assumes that the daemon has already loaded them.
The configuration files consist of `name = value` pairs, one per 1. If [`NIX_USER_CONF_FILES`](./env-common.md#env-NIX_USER_CONF_FILES) is set, then each path separated by `:` will be loaded in reverse order.
line. Other files can be included with a line like `include path`,
where *path* is interpreted relative to the current conf file and a
missing file is an error unless `!include` is used instead. Comments
start with a `#` character. Here is an example configuration file:
Otherwise it will look for `nix/nix.conf` files in `XDG_CONFIG_DIRS` and [`XDG_CONFIG_HOME`](./env-common.md#env-XDG_CONFIG_HOME).
If unset, `XDG_CONFIG_DIRS` defaults to `/etc/xdg`, and `XDG_CONFIG_HOME` defaults to `$HOME/.config` as per [XDG Base Directory Specification](https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html).
1. If [`NIX_CONFIG`](./env-common.md#env-NIX_CONFIG) is set, its contents are treated as the contents of a configuration file.
### File format
Configuration files consist of `name = value` pairs, one per line.
Comments start with a `#` character.
Example:
```
keep-outputs = true # Nice for developers keep-outputs = true # Nice for developers
keep-derivations = true # Idem keep-derivations = true # Idem
```
You can override settings on the command line using the `--option` Other files can be included with a line like `include <path>`, where `<path>` is interpreted relative to the current configuration file.
flag, e.g. `--option keep-outputs false`. Every configuration setting A missing file is an error unless `!include` is used instead.
also has a corresponding command line flag, e.g. `--max-jobs 16`; for
Boolean settings, there are two flags to enable or disable the setting
(e.g. `--keep-failed` and `--no-keep-failed`).
A configuration setting usually overrides any previous value. However, A configuration setting usually overrides any previous value.
you can prefix the name of the setting by `extra-` to *append* to the However, for settings that take a list of items, you can prefix the name of the setting by `extra-` to *append* to the previous value.
previous value. For instance,
For instance,
```
substituters = a b substituters = a b
extra-substituters = c d extra-substituters = c d
```
defines the `substituters` setting to be `a b c d`. This is also defines the `substituters` setting to be `a b c d`.
available as a command line flag (e.g. `--extra-substituters`).
The following settings are currently available: Unknown option names are not an error, and are simply ignored with a warning.
## Command line flags
Configuration options can be set on the command line, overriding the values set in the [configuration file](#configuration-file):
- Every configuration setting has corresponding command line flag (e.g. `--max-jobs 16`).
Boolean settings do not need an argument, and can be explicitly disabled with the `no-` prefix (e.g. `--keep-failed` and `--no-keep-failed`).
Unknown option names are invalid flags (unless there is already a flag with that name), and are rejected with an error.
- The flag `--option <name> <value>` is interpreted exactly like a `<name> = <value>` in a setting file.
Unknown option names are ignored with a warning.
The `extra-` prefix is supported for settings that take a list of items (e.g. `--extra-trusted users alice` or `--option extra-trusted-users alice`).
# Available settings