@@ 4132,7 4132,14 @@ The following options are supported:
@item --update
@itemx -u
-Update distribution source files (package recipes) in place.
+Update distribution source files (package recipes) in place. This is
+usually run from a checkout of the Guix source tree (@pxref{Running
+Guix Before It Is Installed}):
+
+@example
+$ ./pre-inst-env guix refresh -s non-core
+@end example
+
@xref{Defining Packages}, for more information on package definitions.
@item --select=[@var{subset}]
@@ 4157,7 4164,7 @@ In addition, @command{guix refresh} can be passed one or more package
names, as in this example:
@example
-guix refresh -u emacs idutils gcc-4.8.4
+$ ./pre-inst-env guix refresh -u emacs idutils gcc-4.8.4
@end example
@noindent