PRB: "DM0025: Error attaching to process" in Windows 95

• Microsoft Visual C++, 32-bit Editions, versions 5.0, 6.0

SYMPTOMS

In Windows 95, when you use the debugger to attach to a console application that is waiting for user input, you may get the following error message:

DM0025: Error attaching to process.

CAUSE

The debugger times out while waiting for the console application. This problem only occurs on Windows 95.

RESOLUTION

The following steps use the Test sample provided in the MORE INFORMATION section of this article.

1. Start the Test application from Developer Studio or from Windows Explorer. The Test application will display "Start process" and wait for data entry.



2. In Developer Studio, click Start Debug from the Build menu.



3. Click "Attach to Process...". In the Attach to Process dialog box, click the Test process and click OK. Immediately click the application's icon on the Task Bar to activate the Application's window. You may now see the debugger displaying assembly code in Developer Studio with the application loaded in the workspace as if it is ready to debug.



4. Open the test.cpp file in Developer Studio. Set a breakpoint in the line of code as indicated below. At this point if you click the Debug menu, you can only choose "Stop Debugging" or "Break". If you select "Break," you get the following message with an "OK" button:

   All threads are in system calls. It is not possible to break into the debugger at this time.




5. Enter a character followed by the Enter key. The breakpoint is hit and you can debug the application now.

STATUS

This behavior is by design.

MORE INFORMATION

Steps to Reproduce Behavior

1. Create a console project called Test and add the following source file:

   
   // File name test.cpp
   #include <iostream.h>
   
   void  main()
   {
       char ch;
   
       cout << "Start process" << endl;
       cin >> ch;
   
       cout << "Start debugging" << endl; //SET A BREAKPOINT HERE
   
       // Body of code would be here.
   } 




2. Build the project for debug mode.



3. Start the application from developer Studio or from Windows Explorer.



4. In Developer Studio, click Start Debug from the Build menu. Click "Attach to Process...". In the Attach to Process dialog box, click the Test process and click OK. The hour glass icon appears for a while followed by the error message described in the SYMPTOMS section. Note that the error message does not appear immediately.

Additional query words:

Keywords : kberrmsg kbDebug kbide kbVC500 kbVC600
Version : winnt:5.0,6.0
Platform : winnt
Issue type : kbprb