OpenEuphoria

Re: Wierd error (PING ROB)

• Posted by Robert Craig <rds at RapidEuphoria.com> Feb 17, 2005
• 503 views

Pete Lomax wrote:
> Some wierd thing, hSaveStdout is a constant, defined as you will see
> below. But using this constant /*/broke/*/ working code...
> 
> Bizarrely, calling c_func(xGetStdHandle..) inline works, but saving
> this as a constant does not !!!!!!!
> 
> I get the same results on 2.4 and 2.5(a)...
> 
> }}}
<eucode>
> --
> -- odd thing with STD_OUTPUT_HANDLE/constants
> --
> include dll.e
> include machine.e
> 
> constant 
> 	kernel32 = open_dll("kernel32.dll")
> 
> constant 
> 	xGetStdHandle = define_c_func(kernel32, "GetStdHandle",
> 		{C_LONG},		-- 	DWORD  nStdHandle 	// input, output, or
> error device
> 		C_POINTER),		-- HANDLE
> 
> 	xGetConsoleScreenBufferInfo = define_c_func(kernel32,
> "GetConsoleScreenBufferInfo",
> 		{C_POINTER,		--	HANDLE	hConsoleOutput,	// handle of
> console screen buffer
> 		 C_POINTER},	--	PCONSOLE_SCREEN_BUFFER_INFO
> lpConsoleScreenBufferInfo 	// address of screen buffer info.
> 		C_INT)			-- BOOL
> 
> constant  sizeofCSBI		= 18	-- (trust me!)
> constant pCSBI=allocate(sizeofCSBI)
> constant STD_OUTPUT_HANDLE = #FFFFFFF5 -- (-11)
> 
> constant hSaveStdout = c_func(xGetStdHandle,{STD_OUTPUT_HANDLE})
> 
> puts(1,"Hello\n")
> ----!!!! FINE !!!! -----
> 	if not
>
> c_func(xGetConsoleScreenBufferInfo,{c_func(xGetStdHandle,{STD_OUTPUT_HANDLE}),pCSBI})
> then
> ----!!!! BROKEN !!!! -----
> --	if not c_func(xGetConsoleScreenBufferInfo,{hSaveStdout,pCSBI})
> then
> 		?9/0
> 	end if
> </eucode>
{{{


I didn't try to run this code, but it wouldn't surprise me
if you get a different value returned by GetStdHandle 
before the puts() versus after it. The reason is that
I don't create any console window until you do your first output
to the screen. Maybe you could move the puts() before the constant
declaration. The puts() will then be executed before the c_func() 
that's assigned to the constant.

Regards,
   Rob Craig
   Rapid Deployment Software
   http://www.RapidEuphoria.com