FIX: The bool Type Does Not Marshal Correctly from Unmanaged Code

This article has been archived. It is offered "as is" and will no longer be updated.
For a Microsoft Visual Studio .NET 2002 version of this article, see 813488.
When you call unmanaged code that returns a bool type value of false from managed code, the return value may appear as true.
Sometimes the native bool type does not marshal correctly from unmanaged code to managed code.
There are two ways to work around this issue:
  • Change existing native DLLs to use BOOL return types instead of bool.
  • Use DllImport and the platform invoke services to call to the unmanaged DLL.
A supported hotfix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Only apply it to systems that are experiencing this specific problem. This hotfix may receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next Visual Studio .NET 2003 Service Pack that contains this hotfix.

To resolve this problem immediately, contact Microsoft Product Support Services to obtain the fix. For a complete list of Microsoft Product Support Services phone numbers and information about support costs, visit the following Microsoft Web site:Note In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The usual support costs will apply to additional support questions and issues that do not qualify for the specific update in question.
The English version of this fix has the file attributes (or later) that are listed in the following table. The dates and times for these files are listed in coordinated universal time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time tool in Control Panel.
   Date         Time   Version              Size  File name--------------------------------------------------------17-Jun-2003  03:56  13.10.3168.0    2,207,744  C1xx.dll17-Jun-2003  11:30  13.10.3168.0    1,961,984  Feacp.dll        
Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.

Article ID: 823071 - Last Review: 02/27/2014 18:44:18 - Revision: 1.4

  • Microsoft Visual Studio .NET 2003 Academic Edition
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