[RFA/doco] document "set/show interactive-mode"

[Joel Brobecker <brobecker at adacore dot com>]

Eli,

Here is a documentation update for the patch suggested at:
http://www.sourceware.org/ml/gdb-patches/2009-06/msg00403.html

The patch just adds a setting that allows the user to override
the guessing that GDB does in order to determine whether it should
run in interactive or non-interactive mode.

I'm also attaching the code patch, in case you have some comments
about the option and its help documentation itself.

2009-06-23  Joel Brobecker  <brobecker@adacore.com>

        * gdb.texinfo (Other Misc Settings): New node.

I tried to find a good place for it, but nothing really seemed
appropriate.  Peharps if we renamed the "Screen Size" section
to be a little more generic, we could put our new option there.
But it seemed a little artificial, and might make finding these
screen-size related option a little harder to find.  Since the latter
will probably be much more widely used, I didn't think it was the
best thing to do.  Hence the new "misc" section.

OK to apply?

Thanks,
-- 
Joel

commit 1c0d02ae504f32e2728723f62d6b1c290c9c12b0
Author: Joel Brobecker <brobecker@adacore.com>
Date:   Tue Jun 23 10:32:56 2009 -0700

    Add documentation for set/show interactive-mode.
    
        * gdb.texinfo (Other Misc Settings): New node.

diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index 94852ec..f8e77e0 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -17392,6 +17392,7 @@ described here.
 * ABI::                         Configuring the current ABI
 * Messages/Warnings::           Optional warnings and messages
 * Debugging Output::            Optional messages about internal happenings
+* Other Misc Settings::         Other Miscellaneous Settings
 @end menu
 
 @node Prompt
@@ -18021,6 +18022,28 @@ Turns on or off debugging messages for built-in XML parsers.
 Displays the current state of XML debugging messages.
 @end table
 
+@node Other Misc Settings
+@section Other Miscellaneous Settings
+@cindex Miscellaneous Settings
+
+@table @code
+@kindex set interactive-mode
+@item set interactive-mode
+If @code{on}, forces @value{GDBN} to operate interactively.
+If @code{off}, forces @value{GDBN} to operate non-interactively,
+If @code{auto} (the default), @value{GDBN} guesses which mode to use,
+based on whether the debugger was started in a terminal or not.
+
+In the vast majority of cases, the debugger should be able to guess
+correctly which mode should be used.  But this setting can be useful
+in certain specific cases, such as running a MinGW @value{GDBN}
+inside a cygwin window.
+
+@kindex show interactive-mode
+@item show interactive-mode
+Displays whether the debugger is operating in interactive mode or not.
+@end table
+
 @node Extending GDB
 @chapter Extending @value{GDBN}
 @cindex extending GDB

Index: top.c
===================================================================
--- top.c	(.../branches/gdb/FSF/current/gdb/top.c)	(revision 149871)
+++ top.c	(.../trunk/gdb/gdb-head/gdb/top.c)	(revision 149871)
@@ -1288,12 +1308,38 @@ quit_force (char *args, int from_tty)
   exit (exit_code);
 }
 
+/* If OFF, the debugger will run in non-interactive mode, which means
+   that it will automatically select the default answer to all the
+   queries made to the user.  If ON, gdb will wait for the user to
+   answer all queries.  If AUTO, gdb will determine whether to run
+   in interactive mode or not depending on whether stdin is a terminal
+   or not.  */
+static enum auto_boolean interactive_mode = AUTO_BOOLEAN_AUTO;
+
+/* Implement the "show interactive-mode" option.  */
+
+static void
+show_interactive_mode (struct ui_file *file, int from_tty,
+                       struct cmd_list_element *c,
+                       const char *value)
+{
+  if (interactive_mode == AUTO_BOOLEAN_AUTO)
+    fprintf_filtered (file, "\
+Debugger's interactive mode is %s (currently %s).\n",
+                      value, input_from_terminal_p () ? "on" : "off");
+  else
+    fprintf_filtered (file, "Debugger's interactive mode is %s.\n", value);
+}
+
 /* Returns whether GDB is running on a terminal and input is
    currently coming from that terminal.  */
 
 int
 input_from_terminal_p (void)
 {
+  if (interactive_mode != AUTO_BOOLEAN_AUTO)
+    return interactive_mode == AUTO_BOOLEAN_TRUE;
+
   if (gdb_has_a_terminal () && instream == stdin)
     return 1;
 
@@ -1625,6 +1675,19 @@ Use \"on\" to enable the notification, a
 			   show_exec_done_display_p,
 			   &setlist, &showlist);
 
+  add_setshow_auto_boolean_cmd ("interactive-mode", class_support,
+                                &interactive_mode, _("\
+Set whether gdb should run in interactive mode or not"), _("\
+Show whether gdb runs in interactive mode"), _("\
+If on, gdb runs in interactive mode and waits for the user to answer\n\
+all its queries.  If off, gdb runs in non-interactive mode and\n\
+automatically assumes the default answer to all its queries.  If auto\n\
+(which is the default), automatically determine which mode to use based\n\
+on the standard input settings"),
+                        NULL,
+                        show_interactive_mode,
+                        &setlist, &showlist);
+
   add_setshow_filename_cmd ("data-directory", class_maintenance,
                            &gdb_datadir, _("Set GDB's data directory."),
                            _("Show GDB's data directory."),