Erik,

>DECLARE INTEGER GetSystemTime IN win32api STRING @
>cBuff=SPACE(40)
>=GetSystemTime(@cBuff)
>
>
>Well. I'm a bit confused here how they got that cBuff has to be of size 40, when each word is only a size 2 and there is only 8 words, which I see as size 8*2 = 16. It says that you must create a 40-byte string buffer. Why?

16 bytes is plenty, it's just sloppy code on the sample. As long as the buffer is allocated the correct size or larger it'll work.

>But back to my function in the DLL and its structure, which looks like this
>

>typedef struct _INITDATA
>{
>  DWORD dwSize;
>  DWORD dwVersionMajor;
>  DWORD dwVersionMinor;
>  DWORD dwVersionBuild;
>  DWORD dwOptions;
>  DWORD dwReserved1;
>  DWORD dwReserved2;
>  char  szDescription[MAXDESCRIPTIONLENGTH+1];
>
>}  INITDATA, FAR* LPINITDATA;
>

>
>All I need is to make sure that dwSize is the value of the size of the structure. Since it is a Double Word I would imagine the have size of 4 so I tried following (MAXDESCRIPTIONLENGTH is 128) strings
>

>chr(157)+chr(0)+chr(0)+chr(0)+replicate(chr(0), 153)
>chr(0)+chr(157)+chr(0)+chr(0)+replicate(chr(0), 153)
>chr(0)+chr(0)+chr(157)+chr(0)+replicate(chr(0), 153)
>chr(0)+chr(0)+chr(0)+chr(157)+replicate(chr(0), 153)
>

>Or chr(156) and 152 replicated chr(0)'s or chr(32)'s.

Use these functions to convert your data around for structs like these:

* ConvertAPI.prg 08-Oct-97 

* these functions convert to/from internal binary storage

function ToWord( pnNumber )
local lnMSB, lnLSB
lnMSB = int( pnNumber / 256 )  && most significant byte
lnLSB = pnNumber % 256  && least significant byte
return chr( lnLSB ) + chr( lnMSB )

function ToLong( pnNumber )
local lnMSW, lnLSW
lnMSW = int( pnNumber / 65536 )  && most significant word
lnLSW = pnNumber % 65536  && least significant word
return ToWord( lnLSW ) + ToWord( lnMSW )

function FromWord( pcBuffer )
return asc( substr( pcBuffer, 2, 1 ) ) * 256 + asc( left( pcBuffer, 1 ) )

function FromLong( pcBuffer )
local lnNegative

if ( bitand( 0x80, asc( substr( pcBuffer, 3, 1 ) ) ) = 0x80 )
   lnNegative = -1
   pcBuffer = left( pcBuffer, 2 ) + chr( bitand( asc( substr( pcBuffer, 3, 1 ) ), 0x7f ) ) + right( pcBuffer, 1 )
else
   lnNegative = 1
endif
return lnNegative * FromWord( substr( pcBuffer, 3, 2 ) ) * 65536 + FromWord( left( pcBuffer, 2 ) )

Then you'd simply:

szDescription = replicate( 0, MAXDESCRIPTIONLENGTH+1 )
lcBuffer = ToLong( dwSize ) + ;
           ToLong( dwVersionMajor ) + ;
           ToLong( dwVersionMinor ) + ;
           ToLong( dwVersionBuild ) + ;
           ToLong( dwOptions ) + ;
           ToLong( dwReserved1 ) + ;
           ToLong( dwReserved2 ) + ;
           szDescription

And pass lcBuffer to your DLL.