* gdb.texinfo (Hooks): Document the new post-hook functionality.

	From Steven Johnson <sbjohnson@ozemail.com.au>.

diff --git a/gdb/doc/ChangeLog b/gdb/doc/ChangeLog
index fd9566b1b91b0a7a450b998914e313657d1235cf..1dc783e5eb671e8f39041de15f788cc80cd06991 100644 (file)
--- a/gdb/doc/ChangeLog
+++ b/gdb/doc/ChangeLog
@@ -1,3 +1,8 @@
+2000-09-26  Eli Zaretskii  <eliz@is.elta.co.il>
+
+       * gdb.texinfo (Hooks): Document the new post-hook functionality.
+       From Steven Johnson <sbjohnson@ozemail.com.au>.
+
 2000-08-10  Mark Kettenis  <kettenis@gnu.org>
 
        * gdbint.texinfo (Overall Structure): Spelling fix.

diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index 1f4e95ec6281bdbdba9d42ec27e726c41fae19e6..2aee191f2f1191e22307785c27d70504bde66af7 100644 (file)
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -11859,12 +11859,30 @@ messages when used in a user-defined command.
 @section User-defined command hooks
 @cindex command hooks
 @cindex hooks, for commands
+@cindex hooks, pre-command
 
-You may define @emph{hooks}, which are a special kind of user-defined
+@kindex hook
+@kindex hook-
+You may define @dfn{hooks}, which are a special kind of user-defined
 command.  Whenever you run the command @samp{foo}, if the user-defined
 command @samp{hook-foo} exists, it is executed (with no arguments)
 before that command.
 
+@cindex hooks, post-command
+@kindex hookpost
+@kindex hookpost-
+A hook may also be defined which is run after the command you executed.
+Whenever you run the command @samp{foo}, if the user-defined command
+@samp{hookpost-foo} exists, it is executed (with no arguments) after
+that command.  Post-execution hooks may exist simultaneously with
+pre-execution hooks, for the same command.
+
+It is valid for a hook to call the command which it hooks.  If this
+occurs, the hook is not re-executed, thereby avoiding infinte recursion.
+
+@c It would be nice if hookpost could be passed a parameter indicating
+@c if the command it hooks executed properly or not.  FIXME!
+
 @kindex stop@r{, a pseudo-command}
 In addition, a pseudo-command, @samp{stop} exists.  Defining
 (@samp{hook-stop}) makes the associated commands execute every time
@@ -11889,6 +11907,25 @@ handle SIGLARM pass
 end
 @end example
 
+As a further example, to hook at the begining and end of the @code{echo}
+command, and to add extra text to the beginning and end of the message, 
+you could define:
+
+@example
+define hook-echo
+echo <<<---
+end
+
+define hookpost-echo
+echo --->>>\n
+end
+
+(@value{GDBP}) echo Hello World
+<<<---Hello World--->>>
+(@value{GDBP})
+
+@end example
+
 You can define a hook for any single-word command in @value{GDBN}, but
 not for command aliases; you should define a hook for the basic command
 name, e.g.  @code{backtrace} rather than @code{bt}.