@end defvar
@defvar{host}
-Contains the name that the user entered for the host. Since many things
-that the user could enter would map to the same output from
-@code{config.sub}, this variable is innappropriate to use for picking
-available configurations. For that, use @code{host_cpu},
-@code{host_vendor}, and/or @code{host_os}. This variable is useful,
-however, for error messages.
+Contains the full configuration name (generated by the script
+@file{config.sub} from the name that the user entered) for the host.
+This is a three-part name of the form
+
+@example
+@var{cpu}-@var{vendor}-@var{os}
+@end example
+
+@noindent
+There are separate variables @code{host_cpu}, @code{host_vendor}, and
+@code{host_os} that you can use to test each of the three parts; this
+variable is useful, however, for error messages, and for testing
+combinations of the three components.
@end defvar
@defvar{host_cpu}
@end defvar
@defvar{target}
-Contains the name that the user entered for the target. Since
-many things that the user could enter would map to the same canonical
-triple, this variable is innappropriate to use for picking available
-configurations. For that, use @code{target_cpu}, @code{target_vendor},
-and/or @code{target_os}. This variable is useful, however, for error
-messages.
+Contains the full configuration name (generated by the script
+@file{config.sub} from the name that the user entered) for the target.
+This is a three-part name of the form
+
+@example
+@var{cpu}-@var{vendor}-@var{os}
+@end example
+
+@noindent
+There are separate variables @code{target_cpu}, @code{target_vendor}, and
+@code{target_os} that you can use to test each of the three parts; this
+variable is useful, however, for error messages, and for testing
+combinations of the three components.
@end defvar
@defvar{target_cpu}