Question

I’m trying to use the TRACE macro to send the file name to the output window. The following compiles, but when it executes, instead of the desired output, I get an error in the output window:

TRACE(_T("Trace test.\r\n\tError: %d\r\n\tFile: %s\r\n\tLine: %d\r\n"), ERROR_SUCCESS, __FILE__, __LINE__);

Produces error:

_CrtDbgReport: String too long or IO ErrorFirst-chance exception at 0x7c812afb in MyApp.exe: Microsoft C++ exception: long at memory location 0x0012fe18..

I’m sure it has to do with the __FILE__ macro, but I’m not sure what exactly is wrong. Does anyone know how get this working? Thanks.

Answer 1

Isnt it that you need a wide string version of FILE to get that right ?

#define WIDEN2(x) L ## x
#define WIDEN(x) WIDEN2(x)
#define __WFILE__ WIDEN(__FILE__)
wchar_t *pwsz = __WFILE__;

wprintf(pwsz)

// Function to split path into file and directory parts..
void ExtractFileNameFromPath( const std::wstring &_sPath,std::wstring &_sFilename,std::wstring &_sDirectory)
{
    int iPos = _sPath.rfind('\\');
    if( iPos == std::_tstring::npos) iPos = _sPath.rfind(TCHAR("/"));
    if( iPos != std::_tstring::npos) 
    { _sFilename = _sPath.substr(iPos + 1); _sDirectory = _sPath.substr(0,iPos); }
    else _sFilename = _sPath;
    nsStringTools::Trim(_sFilename);
    nsStringTools::Trim(_sDirectory);
    if(_sDirectory[_sDirectory.length()-1] != _T('\\'))
        _sDirectory += _T("\\");
}