diff options
Diffstat (limited to 'doc/manual/src')
| -rw-r--r-- | doc/manual/src/language/advanced-attributes.md | 17 | ||||
| -rw-r--r-- | doc/manual/src/language/derivations.md | 5 |
2 files changed, 15 insertions, 7 deletions
diff --git a/doc/manual/src/language/advanced-attributes.md b/doc/manual/src/language/advanced-attributes.md index 4907f7457..a5ad47a93 100644 --- a/doc/manual/src/language/advanced-attributes.md +++ b/doc/manual/src/language/advanced-attributes.md @@ -274,18 +274,21 @@ Derivations can declare some infrequently used optional attributes. - [`__structuredAttrs`]{#adv-attr-structuredAttrs}\ If the special attribute `__structuredAttrs` is set to `true`, the other derivation - attributes are serialised in JSON format and made available to the - builder via the file `.attrs.json` in the builder’s temporary - directory. This obviates the need for [`passAsFile`](#adv-attr-passAsFile) since JSON files - have no size restrictions, unlike process environments. + attributes are serialised into a file in JSON format. The environment variable + `NIX_ATTRS_JSON_FILE` points to the exact location of that file both in a build + and a [`nix-shell`](../command-ref/nix-shell.md). This obviates the need for + [`passAsFile`](#adv-attr-passAsFile) since JSON files have no size restrictions, + unlike process environments. It also makes it possible to tweak derivation settings in a structured way; see [`outputChecks`](#adv-attr-outputChecks) for example. As a convenience to Bash builders, - Nix writes a script named `.attrs.sh` to the builder’s directory - that initialises shell variables corresponding to all attributes - that are representable in Bash. This includes non-nested + Nix writes a script that initialises shell variables + corresponding to all attributes that are representable in Bash. The + environment variable `NIX_ATTRS_SH_FILE` points to the exact + location of the script, both in a build and a + [`nix-shell`](../command-ref/nix-shell.md). This includes non-nested (associative) arrays. For example, the attribute `hardening.format = true` ends up as the Bash associative array element `${hardening[format]}`. diff --git a/doc/manual/src/language/derivations.md b/doc/manual/src/language/derivations.md index 79a09122a..e4a2fe714 100644 --- a/doc/manual/src/language/derivations.md +++ b/doc/manual/src/language/derivations.md @@ -123,6 +123,11 @@ The builder is executed as follows: - `NIX_STORE` is set to the path of the top-level Nix store directory (typically, `/nix/store`). + + - `NIX_ATTRS_JSON_FILE` & `NIX_ATTRS_SH_FILE` if `__structuredAttrs` + is set to `true` for the dervation. A detailed explanation of this + behavior can be found in the + [section about structured attrs](./advanced-attributes.md#adv-attr-structuredAttrs). - For each output declared in `outputs`, the corresponding environment variable is set to point to the intended path in the |