changes to new pattern substitution replacement; documentation updates

RBASH

@@ -40,10 +40,10 @@ spawned to execute the script.
 The restricted shell mode is only one component of a useful restricted
 environment.  It should be accompanied by setting 'PATH' to a value that
 allows execution of only a few verified commands (commands that allow
-shell escapes are particularly vulnerable), leaving the user in a
-non-writable directory other than his home directory after login, not
-allowing the restricted shell to execute shell scripts, and cleaning the
-environment of variables that cause some commands to modify their
+shell escapes are particularly vulnerable), changing the current
+directory to a non-writable directory other than '$HOME' after login,
+not allowing the restricted shell to execute shell scripts, and cleaning
+the environment of variables that cause some commands to modify their
 behavior (e.g., 'VISUAL' or 'PAGER').
 
 Modern systems provide more secure ways to implement a restricted