Mobile

R.Bischoff | C++
 
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BUG: LNK2019 When Building For Pocket PC Emulation

SYMPTOMS

When building an application for Pocket PC emulation that uses the Windows CE operating system functions, errors similar to the following may be encountered:

<filename>.obj : error LNK2019: unresolved external symbol _CeDeleteDatabase referenced in function <function>

CAUSE

These operating system functions use the _stdcall calling convention, but the compiler is declaring them as _cdecl. This problem occurs with the Windows CE Platform SDK for Pocket PC because the functions are incorrectly declared in the Windbase.h file without a linkage type.

RESOLUTION

Use one of the following workarounds:

• Add the /Gz compiler switch to the configuration's project settings when building for Pocket PC emulation.



-or-




• If the first workaround prevents other functions/libraries from linking in your project, then modify the Windows CE database function declarations in the Windbase.h file. For example, for the error in the "Symptoms" section, change the following declaration
  

  BOOL CeDeleteDatabase (CEOID oid); 

  
  to read:




BOOL WINAPI CeDeleteDatabase (CEOID oid); 

STATUS

Microsoft has confirmed this to be a bug in the Microsoft products listed
at the beginning of this article.

UINT CIrdaPort::FindPortIndex()
{
    // Look into the registry for the IRDA port number

    HKEY hKey = NULL;

    if (RegOpenKeyEx(HKEY_LOCAL_MACHINE, _T("Drivers\\BuiltIn\\IrCOMM"), 0, 0, &hKey) == ERROR_SUCCESS)
    {
        DWORD dwType = 0;
        DWORD dwData = 0;
        DWORD dwSize = sizeof(dwData);

        if (RegQueryValueEx(hKey, _T("Index"), NULL, &dwType, (LPBYTE) &dwData, &dwSize) == ERROR_SUCCESS)
        {
            if (dwType == REG_DWORD && dwSize == sizeof(dwData))
            {
                RegCloseKey(hKey);
                                
                return (UINT) dwData;
            }
        }

        RegCloseKey(hKey);
    }

    return 0;
}

<br />
TCHAR szReturn[1024];<br />
<br />
GetPrivateProfileString(_T("YourSection"),<br />
                        _T("YourKey"),<br />
                        _T("YourDefault"),<br />
                        szReturn,<br />
                        sizeof(szReturn) / sizeof(TCHAR),<br />
                        _T("YourPath\YourIniFile.ini"));<br />
<br />
AfxMessageBox(szReturn);<br />

<br />
DWORD GetPrivateProfileString(<br />
  LPCTSTR lpAppName,        // section name<br />
  LPCTSTR lpKeyName,        // key name<br />
  LPCTSTR lpDefault,        // default string<br />
  LPTSTR lpReturnedString,  // destination buffer<br />
  DWORD nSize,              // size of destination buffer<br />
  LPCTSTR lpFileName        // initialization file name<br />
);<br />