WriteFile help (Win32).

This is my first real use of the win32 api for file i/o and I can't seem to get it to work.

The goal is to save an xml file with some config settings when the program exits, but I can't seem to get the stupid file to write anything and I have a feeling I am handling the buffers or the string manipulation wrong.

I'm trying to use the win32 api and not iostream, ect ..

Here's the write file section:

Code:

HANDLE hConfig = NULL;
DWORD dwWrittenBuffer = 0;
TCHAR *szWriteBuffer = NULL;


hConfig = CreateFile(
   _T("config.xml"), 
   GENERIC_WRITE, 
   FILE_SHARE_WRITE,
   NULL,
   CREATE_ALWAYS,
   0,
   0);

if(hConfig != INVALID_HANDLE_VALUE)
{

   lstrcat(szWriteBuffer, _T("<config>"));
   // do rest of stuff when this works
   lstrcat(szWriteBuffer, _T("</config>"));
   WriteFile(hConfig, szWriteBuffer, lstrlen(szWriteBuffer) + 1, &dwWrittenBuffer, 0);
   CloseHandle(hConfig);

}

Unfortunately my config file comes out empty, so I'm stumped how I'm supposed to handle this, I don't wanna just do a buttload of WriteFiles line for line, I'd rather write it all at once using lstrcat on a single buffer, like I said I'm probably doing the buffer all wrong so any help would be appreciated.

In the 2nd to last param you're passing 0. If you look up the values of the possible values, 0 isn't valid.

Try using FILE_ATTRIBUTE_NORMAL there.

Code:

hConfig = CreateFile(
   _T("config.xml"), 
   GENERIC_WRITE, 
   FILE_SHARE_WRITE,
   NULL,
   CREATE_ALWAYS,
   0,
   0);