Fix a documentation for package.build option.

diff --git a/src/doc/book/src/reference/build-scripts.md b/src/doc/book/src/reference/build-scripts.md
index 2c6fe3d8123a15e0246b7314e87f292b546b48fa..a50f3afea159860165f472bb14f8d8af55aef1a7 100644 (file)
--- a/src/doc/book/src/reference/build-scripts.md
+++ b/src/doc/book/src/reference/build-scripts.md
@@ -18,9 +18,10 @@ build = "build.rs"
 
 The Rust file designated by the `build` command (relative to the package root)
 will be compiled and invoked before anything else is compiled in the package,
-allowing your Rust code to depend on the built or generated artifacts. Note that
-if you do not specify a value for `build` but your package root does contains a
-`"build.rs"` file, Cargo will compile and invoke this file for you.
+allowing your Rust code to depend on the built or generated artifacts.
+By default Cargo looks up for `"build.rs"` file in a package root (even if you
+do not specify a value for `build`). Use `build = "custom_build_name.rs"` to specify
+a custom build name or `build = false` to disable automatic detection of the build script.
 
 Some example use cases of the build command are: