* docs/grub.texi (Invoking grub-install): Fix additional outdated claims

and add some clarification.

ChangeLog

@@ -1,3 +1,8 @@
+2011-05-14  Jordan Uggla  <jordan.uggla@gmail.com>
+
+	* docs/grub.texi (Invoking grub-install): Fix additional outdated claims
+	and add some clarification.
+
 2011-05-14  Vladimir Serbinenko  <phcoder@gmail.com>
 
 	* util/grub.d/10_linux.in: Autoload gzio since it's needed on some

docs/grub.texi

@@ -4165,15 +4165,28 @@ Print a summary of the command-line options and exit.
 @item --version
 Print the version number of GRUB and exit.
 
-@item --root-directory=@var{dir}
-Install GRUB images under the directory @var{dir} instead of the root
-directory. This option is useful when you want to install GRUB into a
-separate partition or a removable disk. Here is an example in which
-you have a separate @dfn{boot} partition which is mounted on
-@file{/boot}:
+@item --boot-directory=@var{dir}
+Install GRUB images under the directory @file{@var{dir}/grub/}
+This option is useful when you want to install GRUB into a
+separate partition or a removable disk.
+If this option is not specified then it defaults to @file{/boot}, so
 
 @example
-@kbd{grub-install --root-directory=/boot hd0}
+@kbd{grub-install /dev/sda}
+@end example
+
+is equivalent to
+
+@example
+@kbd{grub-install --boot-directory=/boot/ /dev/sda}
+@end example
+
+Here is an example in which you have a separate @dfn{boot} partition which is 
+mounted on
+@file{/mnt/boot}:
+
+@example
+@kbd{grub-install --boot-directory=/mnt/boot /dev/sdb}
 @end example
 
 @item --recheck