1  DEBUG

   Invokes the OpenVMS Debugger.

   For a complete description of the OpenVMS Debugger, see the VSI
   OpenVMS Debugger Manual.

   To get help on debugger commands from DCL level, type the
   following command:

   $ HELP/LIBRARY=SYS$HELP:DBG$HELP DEBUG

   Format

     DEBUG


2  Heap_Analyzer

   The Heap Analyzer provides a graphical representation of memory
   use in real time. This allows you to quickly identify inefficient
   memory usage in your application such as allocations that are
   made too often, memory blocks that are too large, fragmentation,
   or memory leaks.

   For details on running the Heap Analyzer from within the
   debugger, see the VSI OpenVMS Debugger Manual.

   On OpenVMS Integrity servers, the standalone Heap Analyzer is
   started within the kept debugger using the START HEAP_ANALYZER
   command (see example).

   On OpenVMS Alpha, the standalone Heap Analyzer is started within
   the kept debugger using the RUN/HEAP command.


2  Qualifiers


/CLIENT

   Invokes the DEBUG client Motif interface. From the client, use
   the network binding string displayed by the server at startup
   to establish the connection. The first client to connect to
   the server is the primary client, and controls the number of
   secondary clients allowed to connect to the server.


/KEEP

   Invokes the kept debugger. The kept debugger includes a Run/Rerun
   capability that allows you to debug an image multiple times or
   debug a series of distinct images without exiting the debugger.

   Issuing the DEBUG/KEEP command is the only way to invoke the kept
   debugger.


/RESUME

      /RESUME (default)

   Reinvokes the non-kept debugger after a Ctrl/Y key sequence has
   interrupted the execution of a program you are debugging. (The
   interrupted program must not have been linked with a /NOTRACEBACK
   qualifier on the LINK command.)

   If you issue the DEBUG/RESUME command without a previous Ctrl/Y
   key sequence, no action occurs.


/SERVER

      /SERVER
      [=( [BINDING_INFO=filespec] [,PROTOCOLS=(protocol[,...])]
      )]

   Invokes the DEBUG server. The DEBUG server allows up to 30
   simultaneous connections from clients on the same or remote
   OpenVMS nodes, or from PC nodes running a supported Microsoft[R]
   Windows[R] platform.

   (Optional) If specified, the BINDING_INFO keyword specifies that
   the server binding identification strings are to be written to
   filespec. If not specified, no file is created.

   (Optional) If specified, the PROTOCOLS keyword specifies which
   network protocols should be enabled for connection to the
   DEBUG server. Only the specified protocols are enabled. If not
   specified, all protocols are enabled. The protocol argument can
   be one or more of the following keywords:

      ALL
      [NO]DECNET
      [NO]TCP_IP
      [NO]UDP

   The first client to connect to the server is the primary client.
   A client that connects to the server after the primary client
   establishes the connection is a secondary client. The primary
   client controls the number of secondary clients allowed to
   connect to the server.

   The server displays a series of RPC binding strings that identify
   the port numbers through which the client can connect to the
   server. The port number appears in square brackets ([]) at the
   end of the identification strings.

   When connecting from the client, the simplest port identification
   string consists of the node name of the server followed by the
   port number in square brackets. The following are all valid
   binding identification strings:

      NODNAM[1234]
      NCACN_IP_TCP:16.32.16.25[1112]
      16.32.16.25[1112]
      NCACN_DNET_NSP:63.1004[RPC20A020DD0001]


                                  NOTE

      You must hold the DBG$ENABLE_SERVER identifier in the rights
      database to be able to run the debug server. Exercise care
      when using the debug server. Once a debug server is running,
      anyone on the network has the ability to connect to the
      debug server.

   Before granting the DBG$ENABLE_SERVER identifier, the system
   manager must create it by entering the command DEBUG/SERVER
   from an account with write access to the rights database. The
   system manager needs to do this only once. The system manager
   can then run the Authorize utility to grant the DBG$ENABLE_SERVER
   identifier to the user's account in the rights database.


2  Examples

   1.$ FORTRAN/DEBUG/NOOPTIMIZE WIDGET
     $ LINK/DEBUG WIDGET
     $ RUN WIDGET

                     [ Debugger Banner and Version ]

     %DEBUG-I-INITIAL, language is FORTRAN, module set to WIDGET
     DBG>

     The FORTRAN and LINK commands both specify the /DEBUG qualifier
     to compile the program WIDGET.FOR with debugger symbol table
     information. Because the program has been compiled and linked
     with debug information, the debugger is automatically invoked
     by the image activator upon starting the program with the
     RUN command. No program code has yet been executed when the
     debugger is invoked.

   2.$ FORTRAN/DEBUG/NOOPTIMIZE WIDGET
     $ LINK/DEBUG WIDGET
     $ RUN/NODEBUG WIDGET

       NAME:
       NAME:
       NAME:
     ^Y
     $ DEBUG/RESUME

                  [ Debugger Banner and Version ]

       %DEBUG-I-INITIAL, language is FORTRAN, module set to WIDGET
       DBG>

     The FORTRAN and LINK commands both specify the /DEBUG qualifier
     to compile the program WIDGET.FOR with debugger symbol table
     information. The RUN command begins execution of the image
     WIDGET.EXE, which loops uncontrollably. Ctrl/Y interrupts the
     program, and the DEBUG/RESUME command gives control to the
     debugger.

   3.$ CC/DEBUG/NOOPTIMIZE ECHOARGS
     $ LINK/DEBUG ECHOARGS
     $ ECHO == "$ sys$disk:[]echoargs.exe"
     $ DEBUG/KEEP

                        [ Debugger Banner and Version ]

     DBG> RUN/COMMAND="ECHO"/ARGUMENTS="fa sol la mi"
     %DEBUG-I-INITIAL, language is C, module set to ECHOARGS
     %DEBUG-I-NOTATMAIN, type GO to get to start of main program
     DBG>
        .
        .
        .
     DBG> RERUN/ARGUMENTS="fee fii foo fum"
     %DEBUG-I-INITIAL, language is C, module set to ECHOARGS
     %DEBUG-I-NOTATMAIN, type GO to get to start of main program
     DBG>
        .
        .
        .
     DBG> RUN/ARGUMENTS="a b c" ECHOARGS
     %DEBUG-I-INITIAL, language is C, module set to ECHOARGS
     %DEBUG-I-NOTATMAIN, type GO to get to start of main program
     DBG>

     The CC and LINK commands both specify the /DEBUG qualifier
     to compile the program ECHOARGS.C with debugger symbol table
     information.

     The symbol definition command defines a foreign command for use
     during the debugging session.

     The DEBUG/KEEP command invokes the kept debugger.

     The first RUN command uses the /COMMAND qualifier to specify
     a foreign command to invoke the image file and the /ARGUMENTS
     qualifier to specify a string of arguments.

     The RERUN command reinvokes the same image file and uses the
     /ARGUMENTS qualifier to specify a new string of arguments.

     The second RUN command specifies a new image file and a new
     string of arguments.

     On Integrity server systems, start the Heap Analyzer within the
     kept debugger:

   4.$ debug/keep
     DBG> run/heap 8queens

     or, alternately:

   5.$ debug/keep
     DBG> run 8queens
      .
      .
      .
     DBG> deactivate break/all
     DBG> deactivate watch/all
     DBG> deactivate trace/all
     DBG> start heap_analyzer
     DBG> activate break/all
     DBG> activate watch/all
     DBG> activate trace/all

     Using this method, you must first deactivate all watchpoints,
     breakpoints, and tracepoints before starting the heap analyzer
     with the START HEAP_ANALYZER command. This procedure prevents
     a potential race condition from occurring. After starting the
     heap analyzer, re-activate the breakpoints, watchpoints, and
     trace points.

     On Alpha systems, start the Heap Analyzer within the kept
     debugger:

   6.$  debug/keep
     DBG> run/heap 8queens

   7.$ DEBUG/SERVER=(PROTOCOLS=(TCP_IP,DECNET))

     %DEBUG-I-SPEAK: TCP/IP: YES, DECnet: YES, UDP: NO
     %DEBUG-I-WATCH: Network Binding: ncacn_ip_tcp:16.32.16.25[1112]
     %DEBUG-I-WATCH: Network Binding: ncacn_dnet_nsp:63.1004[RPC20A020DD0001]
     %DEBUG-I-AWAIT: Ready for client connection...

     The DEBUG/SERVER command establishes a connection to the debug
     server, requesting network protocols TCP/IP and DECnet. Note
     that the binding strings are saved in file TEMP.TMP. You can
     use the TYPE command to display the contents of TEMP.TMP.