Hints and tips

Resolving The Problem

When you launch help from the Distributed Debugger, you can choose to have the help displayed in a separate browser window for each help item requested, or you can choose to have the same browser window display each help item as it is requested. To set your preference for this behavior, select File > Preferences > General > Help from the debugger main menu and select or de-select the 'Open help in a separate browser window' checkbox.

Allow the Debugger to complete operations while the busy cursor displays before clicking in any Debugger windows.

If the Debugger user interface is terminated, then the Debugger engine ("derdfsrv" or "derdewd") or the java process may need to be terminated manually. If any of these processes is running when you attempt to restart the Debugger ("idebug"), the attempt may fail

If you attempt to load an invalid program and then close the starting dialog, the Debugger still attempts to load the invalid program. After the timeout, a load failed message appears, even if you have subsequently loaded a valid program.

Editing text values in the various panes requires the user to press Enter when done. Clicking elsewhere in the pane without first pressing Enter will cancel the editing.

If you catch an exception and choose to run the exception, the Debugger UI will no longer respond unless your application hits a breakpoint, runs to completion, or throws another exception.

Changing the toolbar settings (File > Preferences > General > Appearance, Toolbars) may cause erratic Debugger behavior. If you changed them and want to restore the default settings, delete 'Workbook*.ini' and 'Panes.ini' in your 'DbgProf' profile directory. This also applies for remote debugging of OS/390 applications from Windows NT.

Some Unicode characters, such as \u03a9, do not display correctly. The Debugger currently cannot tell if a given character is displayable in the current user font set.

Using the debug help when debugging Java AWT applications may cause the Debugger to hang.

Using a larger font (File > Increase Font) may cause some text to be truncated. To address this problem, either use a smaller font or restart the Debugger, which allows all components to adjust to the larger font.

If a storage or storage monitor view continues to scroll after you have stopped pressing mouse button one, then click again either above or below the slider to cause a single scroll in the opposite direction.

An error message may appear with the message "Invalid object" if your mouse is moved over a deferred monitored expression (an expression that comes from a module which has been already unloaded) in the Monitors view. This message can be ignored.

If you are running the Distributed Debugger user interface on AIX and F1 help calls do not result in help appearing in your Netscape browser, you should upgrade your Netscape version to 4.74 or higher.

Tool tip evaluation uses spaces and punctuation to parse source and, therefore, will only evaluate identifiers and not expressions. If you wish to evaluate more complicated expressions with tool tip, highlight the entire expression in the Source view and then position the mouse pointer to hover over the highlighted expression and see the evaluation.

When viewing a Control or Value pane with expandable items, choosing the Expand All option from the pane's menu in the debugger main menu bar will expand one level of the tree at a time. You must choose Expand All for each subsequent level of the tree that you wish to expand. Choosing Collapse All will collapse all levels of the tree.

General issues

Norton Antivirus must be disabled in order to run the Distributed Debugger on Windows 95/98.

If your platform is the Japanese version of Windows 98 and you encounter problems starting the Debugger using the "idebug" command, shut down the HTTPDL.EXE process, and start the Debugger again.

TCP/IP considerations

The Debugger (and many other Java products) requires TCP/IP to be functioning and that the user be able to 'ping' their own machine hostname (or, the hostname "localhost") even while disconnected from a LAN.

Windows-specific issues

On Windows 2000, in order to use the context-sensitive help of the accompanying product, you need to define a system environment variable called windir and set it to the system root. For example, if your system's root is c:\winnt, then windir=c:\winnt.

To avoid intermittent hangs on Windows 2000, try disabling the Windows Active Desktop. To disable the Active Desktop, do the following:

1. Right-click on your Windows desktop to invoke the 'Display Properties' dialog box
2. In the 'Web' tab, de-select the 'Show Web content on my Active Desktop' checkbox.

Windows NT and 2000 have a limit on the length of command lines (2100+ chars). The "idebug" command typically uses about 350 characters, and so you should ensure that the CLASSPATH environment variable is less than 1750 characters. Results are unpredictable when the combined length of a command and CLASSPATH exceeds this 2100-character limit.

For Windows NT, if you receive an error message about not being able to locate CPPWMTHI.DLL, you should change the setting of the LOCPATH so that %LOCPATH% appears as the first value in the Value field. Set the LOCPATH environment variable in the "User Variables" section of the Environment page of the System Properties window. This ensures you will pick up the System LOCPATH value as well.

If the Debugger user interface ("idebug") displays the message "cannot create XXXX server socket" (where XXXX represents a port number), there may be an old java process still running. Use the Windows NT Task Manager to end it.

When debugging a GUI application on Windows, the debugger may hang when help is requested. To correct this problem, do one of the following:
• If you are using Internet Explorer: Set debugger application preferences so that help is displayed in the same browser window for each help item that is requested, and then start Internet Explorer before requesting help from the debugger. To set the debugger to display help in the same browser window each time help is requested, select File > Preferences > General > Help from the debugger main menu and select the 'Open help in a separate browser window' checkbox.
• If you are using Netscape: Run or step the GUI application that you are debugging, and the help will appear.


If the debugger is unresponsive, except for an alert noise when you click the debugger user interface, try using the keyboard to request a dialog box (for example, type 'CTRL+L' to invoke the Load Program dialog box)and then cancel the dialog box.

When using the Help section of the Application Preferences dialog box (select File > Preferences > General > Help from the debugger main menu), regardless of entries made in the 'Help Browser' and 'Browser Location' fields, your system's default browser may be used when help is launched.

AIX-specific issues

On AIX, if running the user interface (idebug) results in the message "killed" and the user interface does not come up (or shuts down) the likely cause is insufficient system pagefile space.

On AIX, if the LIBPATH environment variable contains /usr/lib, ensure that /usr/lib/threads appears before /usr/lib.

If "Run To Completion" hangs on AIX in a WebSphere Application Server Enterprise Edition environment, you should terminate the client application.

AS/400-specific issues

If you attach to an AS/400 job without specifying the name of the program to debug and run your application to completion, you will not get notified of the application completion. At this point, you can either bring up the 'Attach' or 'Load Program' dialog to start a new debug session, use the HALT button to terminate the current debug session, or terminate the debugger user interface using File > Exit from the debugger menu bar.

When debugging an AS/400 application and using the Source > Change Text File option, specify either a valid local file, or * to use the original AS/400 source file. If you specify an invalid source file name, the displayed view may become corrupted.

Solaris-specific issues

If you examine or retry a signal that occurs in a multithreaded debuggee and then run, the signal will reoccur when the thread that generated it terminates. In this situation, the signal cannot be run or discarded. To escape, you must terminate the debuggee.