---- Reported by joeshaw@novell.com 2007-05-07 16:37:43 MST ----

mdb's list command seems to take gdb syntax, but doesn't match gdb's
behavior in many cases, particularly in keeping a cursor when running
"list" or "list -" repeatedly:

For example:
(mdb) list
 478 
 479                    if (! ExtendedAttribute.Supported) {
 480                            Logger.Log.Warn ("Extended attributes are
not supported on this filesystem.  " +
 481                                             "Performance will suffer
as a result.");
 482                    }
 483 
 484                    if (disable_textcache) {
 485                            Log.Warn ("Running with text-cache disabled!");
 486                            Log.Warn ("*** Snippets will not be
returned for documents indexed in this session.");
 487                    }
 488 
 489                    // Start our memory-logging thread
 490                    if (arg_debug_memory)
 491                            ExceptionHandlingThread.Start (new
ThreadStart (LogMemoryUsage));
 492 
 493                    // Do BEAGLE_EXERCISE_THE_DOG_HARDER-related
processing.
 494                    ExerciseTheDogHarder ();
 495 
 496                    // Initialize GObject type system
 497                    g_type_init ();
(mdb) list
 478 
 479                    if (! ExtendedAttribute.Supported) {
 480                            Logger.Log.Warn ("Extended attributes are
not supported on this filesystem.  " +
 481                                             "Performance will suffer
as a result.");
 482                    }
 483 
 484                    if (disable_textcache) {
 485                            Log.Warn ("Running with text-cache disabled!");
 486                            Log.Warn ("*** Snippets will not be
returned for documents indexed in this session.");
 487                    }
 488 
 489                    // Start our memory-logging thread
 490                    if (arg_debug_memory)
 491                            ExceptionHandlingThread.Start (new
ThreadStart (LogMemoryUsage));
 492 
 493                    // Do BEAGLE_EXERCISE_THE_DOG_HARDER-related
processing.
 494                    ExerciseTheDogHarder ();
 495 
 496                    // Initialize GObject type system
 497                    g_type_init ();
(mdb) 

However, the cursor is correctly moved if you run "list" and then simply
hit enter:

(mdb) list
 478 
 479                    if (! ExtendedAttribute.Supported) {
 480                            Logger.Log.Warn ("Extended attributes are
not supported on this filesystem.  " +
 481                                             "Performance will suffer
as a result.");
 482                    }
 483 
 484                    if (disable_textcache) {
 485                            Log.Warn ("Running with text-cache disabled!");
 486                            Log.Warn ("*** Snippets will not be
returned for documents indexed in this session.");
 487                    }
 488 
 489                    // Start our memory-logging thread
 490                    if (arg_debug_memory)
 491                            ExceptionHandlingThread.Start (new
ThreadStart (LogMemoryUsage));
 492 
 493                    // Do BEAGLE_EXERCISE_THE_DOG_HARDER-related
processing.
 494                    ExerciseTheDogHarder ();
 495 
 496                    // Initialize GObject type system
 497                    g_type_init ();
(mdb) 
 498 
 499                    if (SystemInformation.XssInit ())
 500                            Logger.Log.Debug ("Established a connection
to the X server");
 501                    else
 502                            Logger.Log.Debug ("Unable to establish a
connection to the X server");
 503                    XSetIOErrorHandler (BeagleXIOErrorHandler);
 504 
 505                    // Lower our CPU priority
 506                    SystemPriorities.Renice (7);
 507 
 508                    QueryDriver.Init ();
 509                    Server.Init ();
 510 
 511                    SetupSignalHandlers ();
 512                    Shutdown.ShutdownEvent += OnShutdown;
 513 
 514                    main_loop = new MainLoop ();
 515                    Shutdown.RegisterMainLoop (main_loop);
 516 
 517                    // Defer all actual startup until the main loop is
(mdb) 

The same behavior occurs with "list -" to go backward.



---- Additional Comments From martin@ximian.com 2007-05-09 10:42:00 MST ----

If you type `list' a second time, it's a new command and thus it
starts again.



---- Additional Comments From joeshaw@novell.com 2007-05-09 11:45:26 MST ----

This doesn't match gdb behavior, and since mdb otherwise "feels" a lot
like gdb, I think this is a bug:

(gdb) list
2       #include <sys/types.h>
3
4       int
5       main (int argc, char *argv[])
6       {
7               printf ("hello world\n");
8               printf ("UID: %d\n", getuid ());
9               printf ("Effective UID: %d\n", geteuid ());
10
11              return 0;
(gdb) list
12      }
(gdb)

(gdb) list -
2       #include <sys/types.h>
3
4       int
5       main (int argc, char *argv[])
6       {
7               printf ("hello world\n");
8               printf ("UID: %d\n", getuid ());
9               printf ("Effective UID: %d\n", geteuid ());
10
11              return 0;
(gdb) list -
1       #include <unistd.h>
(gdb)

And lastly, the help:
List specified function or line.
With no argument, lists ten more lines after or around previous listing.
"list -" lists the ten lines before a previous ten-line listing.
One argument specifies a line, and ten lines are listed around that line.
Two arguments with comma between specify starting and ending lines to
list.
Lines can be specified in these ways:
  LINENUM, to list around that line in current file,
  FILE:LINENUM, to list around that line in that file,
  FUNCTION, to list around beginning of that function,
  FILE:FUNCTION, to distinguish among like-named static functions.
  *ADDRESS, to list around the line containing that address.
With two args if one is empty it stands for ten lines away from the
other arg.





---- Additional Comments From joeshaw@novell.com 2007-05-09 11:50:28 MST ----

BTW, I would suggest matching the gdb behavior and adding a new way of
listing from the current running position, like "list ."  (The lack of
a way to do this in gdb short of jumping up a stack frame and back
down has always annoyed me.)



---- Additional Comments From joeshaw@novell.com 2007-05-10 12:57:06 MST ----

I'm reopening this as a wishlist bug and attaching a patch which
implements it.  It keeps the source code state between "list"
invocations and resets it if you run "list ."



---- Additional Comments From joeshaw@novell.com 2007-05-10 12:57:34 MST ----

Created an attachment (id=171926)
Patch to implement this behavior


Imported an attachment (id=171926)

Unknown operating system unknown. Setting to default OS "Other".