(minor) put some comments to show how to use the Process API.

src/requests/register.cr

@@ -65,6 +65,9 @@ class AuthD::Request
 						# ENV
 						{ "HOME" => "/", "LOGIN" => u_login, "TOKEN" => u_activation_key },
 						true # clear environment
+						# input:   Process::Redirect::Inherit,
+						# output:  Process::Redirect::Inherit,
+						# error:   Process::Redirect::Inherit
 					).success?
 					raise "cannot contact user #{u_login} address #{u_email}"
 				end