diff --git a/docs/Formula-Cookbook.md b/docs/Formula-Cookbook.md index e82499dc1620ec4e211bfc5b64e277e21c1494e2..3c22509af6577425c0b37c8f275ba6792c309442 100644 --- a/docs/Formula-Cookbook.md +++ b/docs/Formula-Cookbook.md @@ -732,9 +732,9 @@ Homebrew provides two formula DSL methods for launchd plist files: Homebrew has multiple levels of environment variable filtering which affects variables available to formulae. -Firstly, the overall environment in which Homebrew runs is filtered to avoid environment contamination breaking from-source builds (<https://github.com/Homebrew/brew/issues/932>). In particular, this process filters all but the given whitelisted variables, but allows environment variables prefixed with `HOMEBREW_`. The specific implementation can be seen in [`bin/brew`](https://github.com/Homebrew/brew/blob/master/bin/brew). +Firstly, the overall environment in which Homebrew runs is filtered to avoid environment contamination breaking from-source builds (<https://github.com/Homebrew/brew/issues/932>). In particular, this process filters all but the given whitelisted variables, but allows environment variables prefixed with `HOMEBREW_`. The specific implementation can be seen in [`bin/brew`](https://github.com/Homebrew/brew/blob/master/bin/brew). -The second level of filtering removes sensitive environment variables (such as credentials like keys, passwords or tokens) to avoid malicious subprocesses obtaining them (<https://github.com/Homebrew/brew/pull/2524>). This has the effect of preventing any such variables from reaching a formula's Ruby code as they are filtered before it is called. The specific implementation can be seen in the [`ENV.clear_sensitive_environment!` method](https://github.com/Homebrew/brew/blob/master/Library/Homebrew/extend/ENV.rb). +The second level of filtering removes sensitive environment variables (such as credentials like keys, passwords or tokens) to avoid malicious subprocesses obtaining them (<https://github.com/Homebrew/brew/pull/2524>). This has the effect of preventing any such variables from reaching a formula's Ruby code as they are filtered before it is called. The specific implementation can be seen in the [`ENV.clear_sensitive_environment!` method](https://github.com/Homebrew/brew/blob/master/Library/Homebrew/extend/ENV.rb). In summary, environment variables used by a formula need to conform to these filtering rules in order to be available.