anchor.diff:       It is passed a void* user context parameter and returns an int.
      *}
     PSDL_ThreadFunction = ^TSDL_ThreadFunction;
  -  TSDL_ThreadFunction = function(data: Pointer): Integer;
  +  TSDL_ThreadFunction = function(data: Pointer): Integer cdecl;
   
     {* The SDL thread ID *}
     TSDL_ThreadID = LongWord;
  
positive.code:    *}
  
     TRead = function(context: PSDL_RWops; ptr: Pointer; size: size_t; maxnum: size_t): size_t; {$IFNDEF GPC} cdecl; {$ENDIF}
     
    {**
     *  Write exactly num objects each of size size from the area
     *  pointed at by ptr to data stream.
  
negative.code:    *  0 if successful or -1 on write error when flushing data.
     *}
  
    TClose =  function(context: PSDL_RWops): SInt32;{$IFNDEF GPC} cdecl; {$ENDIF}
  
    TStdio = record
      autoclose: TSDL_Bool;
  	fp: file;
  