FIX: _getmbp CRT Function Does Not Return Correct Value

• The C Run-time (CRT) included with:

      - Microsoft Visual C++, 32-bit Editions, versions 5.0sp1, 5.0sp2
  

• Microsoft Visual Studio versions 97, 97sp1, 97sp2

SYMPTOMS

The C Run-time (CRT) Library function _getmbcp is supposed to return 0 if a single-byte code page is in use. However, this is not true with the CRT Library shipped with Visual C++ 5.0 in Visual Studio 97 Service Pack 1 and Service Pack 2. The function returns the current code page value irrespective of whether it is a single byte or multi byte code page. This behavior breaks existing programs that were using this call primarily to query whether a single-byte code page is active.

STATUS

Microsoft has confirmed this to be a bug in the Microsoft products listed at the beginning of this article. This bug has been fixed in Visual Studio 97 Service Pack 3.

For more information, please see the following article in the Microsoft Knowledge Base:

   ARTICLE-ID: Q170365
   TITLE     : INFO: Visual Studio 97 Service Packs - What, Where, and Why

MORE INFORMATION

The following sample program demonstrates the bug:

   //sample.cpp
   /* Compiler options: none */
   #include <mbctype.h>
   #include <stdio.h>

   main()
   {
     printf("The return value from _getmbcp is= %d \n", _getmbcp());
     return 0;
   }

Keywords          : CRTIss VS97FixlistSP3 VS97FixlistSP2 VS97FixlistSP1
Version           : WINNT:5.0sp1,5.0sp2,97,97sp1,97sp2
Platform          : winnt
Issue type        : kbbug
Solution Type     : kbfix kbservicepack