ddd(1)                             GNU Tools                            ddd(1)

       ddd - The Data Display Debugger

       ddd    [--help] [--gdb] [--dbx] [--ladebug] [--wdb] [--xdb] [--jdb]
              [--pydb] [--perl] [--debugger name] [--[r]host
              [[username@]hostname]] [--trace] [--version] [--configuration]
              [options...] [prog[core|procID]]

       but usually just

       ddd    program

       DDD is a graphical front-end for GDB and other command-line debuggers.
       Using DDD, you can see what is going on “inside” another program while
       it executes—or what another program was doing at the moment it crashed.

       DDD can do four main kinds of things (plus other things in support of
       these) to help you catch bugs in the act:

       • Start your program, specifying anything that might affect its

       • Make your program stop on specified conditions.

       • Examine what has happened, when your program has stopped.

       • Change things in your program, so you can experiment with correcting
         the effects of one bug and go on to learn about another.

       “Classical” UNIX debuggers such as the GNU debugger (GDB) provide a
       command-line interface and a multitude of commands for these and other
       debugging purposes.  DDD is a comfortable graphical user interface
       around an inferior GDB, DBX, Ladebug, XDB, JDB, Python debugger, or
       Perl debugger.

       DDD is invoked with the shell command ddd.  You can open a program to
       be debugged using `File→Open Program' (the `Open Program' item in the
       `File' menu.  You can get online help at any time using the `Help'
       menu; for the first steps, try `Help→What Now?'.  Quit DDD using

       More information on DDD is contained in the DDD Manual.  You can read
       the text-only version in DDD (via `Help→DDD Reference') or in Emacs (as
       Info file).  Full-fledged HTML, PostScript, and PDF versions are
       available online via the DDD WWW page,


       These are the most important options used when starting DDD.  All
       options may be abbreviated, as long as they are unambiguous; single
       dashes may also be used.  DDD also understands the usual X options such
       as `-display' or `-geometry'; see X(1) for details.

       All arguments and options not handled by DDD are passed to the inferior
       debugger.  To pass an option to the inferior debugger that conflicts
       with an X option, or with a DDD option listed here, use the
       `--debugger' option, below.

              Show the DDD configuration settings and exit.

       --dbx  Run the DBX debugger as inferior debugger.

       --debugger name
              Invoke the inferior debugger name.  This is useful if you have
              several debugger versions around, or if the inferior debugger
              cannot be invoked as `gdb', `dbx', `xdb', `jdb', `pydb', or
              `perl' respectively.
              This option can also be used to pass options to the inferior
              debugger that would otherwise conflict with DDD options.  For
              instance, to pass the option `-d directory' to XDB, use:

                ddd --debugger "xdb -d directory"

              If you use the `--debugger' option, be sure that the type of
              inferior debugger is specified as well.  That is, use one of the
              options `--gdb', `--dbx', `--xdb', `--jdb' `--pydb', or `--perl'
              (unless the default setting works fine).

       --gdb  Run the GDB debugger as inferior debugger.

       --help Give a list of frequently used options.  Show options of the
              inferior debugger as well.

       --host [username@]hostname
              Invoke the inferior debugger directly on the remote host
              hostname.  If username is given and the `--login' option is not
              used, use username as remote user name.

       --jdb  Run JDB as inferior debugger.

              Run Ladebug as inferior debugger.

       --perl Run Perl as inferior debugger.

       --pydb Run PYDB as inferior debugger.

       --rhost [username@]hostname
              Run the inferior debugger interactively on the remote host
              hostname.  If username is given and the `--login' option is not
              used, use username as remote user name.

              Show the interaction between DDD and the inferior debugger on
              standard error.  This is useful for debugging DDD.  If `--trace'
              is not specified, this information is written into
              `$HOME/.ddd/log', such that you can also do a post-mortem

              Show the DDD version and exit.

       --wdb  Run the WDB debugger as inferior debugger.

       --xdb  Run XDB as inferior debugger.

       A full list of options, including important options of the inferior
       debugger, can be found in the DDD manual.

       X(1), gdb(1), dbx(1), wdb(1), xdb(1), perldebug(1)

       `ddd' entry in info.

       `gdb' entry in info.

       Debugging with DDD: User's Guide and Reference Manual, by Andreas

       Using GDB: A Guide to the GNU Source-Level Debugger, by Richard M.
       Stallman and Roland H. Pesch.

       Java Language Debugging, at http://java.sun.com/ (and its mirrors) in

       The Python Language, at http://www.python.org/ and its mirrors.

       DDD—A Free Graphical Front-End for UNIX Debuggers, by Andreas Zeller
       and Dorothea Luetkehaus, Computer Science Report 95-07, Technische
       Universitaet Braunschweig, 1995.

       DDD – ein Debugger mit graphischer Datendarstellung, by Dorothea
       Luetkehaus, Diploma Thesis, Technische Universitaet Braunschweig, 1994.

       The DDD FTP site,


       The DDD WWW page,


       The DDD Mailing List,


       For more information on this list, send a mail to

          ddd-request@gnu.org .

       This manual page is Copyright © 2001 Universitaet Passau, Germany and ©
       2001-2004 Free Software Foundation, Inc.

       Permission is granted to make and distribute verbatim copies of this
       manual page provided the copyright notice and this permission notice
       are preserved on all copies.

       Permission is granted to copy and distribute modified versions of this
       manual page under the conditions for verbatim copying, provided that
       the entire resulting derived work is distributed under the terms of a
       permission notice identical to this one.

       Permission is granted to copy and distribute translations of this
       manual page into another language, under the above conditions for
       modified versions, except that this permission notice may be included
       in translations approved by the Free Software Foundation instead of in
       the original English.

DDD 3.3.12                        2001-01-15                            ddd(1)