PRB: Windows Application Displays Hourglass, then Exits

The information in this article applies to:

• Microsoft C/C++ for MS-DOS, version 7.0
• Microsoft Visual C++ for Windows, versions 1.0, 1.5, 1.51, and 1.52

SYMPTOMS

Running a C or C++ application for Windows that calls a DLL built with C/C++ for MS-DOS, version 7.0, or Visual C++ for Windows, versions 1.0 and 1.5, exits after briefly displaying the hourglass cursor; the main window for the application is not displayed. This can occur when running the application from File Manager or when attempting to run it from within a debugger.

CAUSE

If the application was linked with an import library for a DLL, and the DLL was built without including a HEAPSIZE statement in the .DEF file or HEAPSIZE was set to 0, this behavior can occur. The default .DEF file that the Visual C++ Workbench creates for Windows DLLs sets HEAPSIZE to 1024. It only adds a .DEF file when the project does not include one already. So this problem could occur if a user creates a .DEF file and does not include a HEAPSIZE, sets HEAPSIZE to 0, or modifies the HEAPSIZE statement in the default .DEF file.

Another thing that causes this problem to occur is naming your project using a name reserved by Windows for one of its system components. For more information, please see the following article in the Microsoft Knowledge Base:

   ARTICLE-ID: Q116492
   TITLE     : PRB: Debugger Cannot Debug DISPLAY.EXE

RESOLUTION

Including a HEAPSIZE statement in the .DEF file for the DLL and specifying a non-zero value negates the problem.

MORE INFORMATION

The Windows loader detects that an error occurred when trying to run the application, and this is why the application exits immediately. As part of loading the application, Windows, using an import library, loads any DLLs to which that application is implicitly linked.

The C/C++ run-time startup code for DLLs calls the Windows function "LocalInit" to initialize the local heap for the DLL. The LocalInit fails when the HEAPSIZE is unspecified or set at 0. When the call to LocalInit fails, the startup code returns an error indication to Windows and the application fails to load.