🚀 go-pugleaf

If you look at the docs on that function one of the reasons for the invalid
parameter return value is for the situation where you do not own the memory
at the address given.  By convention your program does not own the NULL
address, it is an invalid addres, so the error makes sense.  Put the address
of something in there.  Here is an example I ran just to illustrate:

  ------------------
  C:\Documents and Settings\Administrator\My Documents\Lookat\Temp
  >type temp5.cpp

  #include <windows.h>
  #include <iphlpapi.h>
  #include <stdio.h>

  const char *GetReason(DWORD val)
    {
    char *msg;

    switch (val)
      {
      case ERROR_BUFFER_OVERFLOW :
        msg = "ERROR_BUFFER_OVERFLOW";
        break;
      case ERROR_INVALID_PARAMETER :
        msg = "ERROR_INVALID_PARAMETER";
        break;
      default :
        msg = "Other message";
        break;
      }

    return msg;
    }

  int main()
    {
    unsigned long ulAdapterSize=0;

    DWORD result = GetAdaptersInfo(NULL, &ulAdapterSize);

    printf("NULL gives %s\n", GetReason(result));

    char c;

    result = GetAdaptersInfo((PIP_ADAPTER_INFO) &c, &ulAdapterSize);
    printf("&char gives %s\n", GetReason(result));

    return 0;
    }

  C:\Documents and Settings\Administrator\My Documents\Lookat\Temp
  >ver

  Microsoft Windows XP [Version 5.1.2600]

  C:\Documents and Settings\Administrator\My Documents\Lookat\Temp
  >temp5
  NULL gives ERROR_BUFFER_OVERFLOW
  &char gives ERROR_INVALID_PARAMETER

  C:\Documents and Settings\Administrator\My Documents\Lookat\Temp
  >
  ------------------

.  Ed

> derek wrote in message
> news:40237638$1@newsgroups.borland.com...
>
> Does any one know why the call to GetAdaptersInfo returns:
>
> ERROR_BUFFER_OVERFLOW on my Win2k machine...but
> ERROR_INVALID_PARAMETER on an XP machine?
>
> I'm using CB5 pro on both machines.
>
> ULONG ulAdapterSize=0;
>
> if(GetAdaptersInfo(NULL, &ulAdapterSize) ==
>  ERROR_BUFFER_OVERFLOW)
> {
> <--SNIP-->