OpenEuphoria

1. Wierd error (PING ROB)

• Posted by Pete Lomax <petelomax at blueyonder.co.uk> Feb 17, 2005
• 497 views

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)...

--
-- 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

3. Re: Wierd error (PING ROB)

• Posted by Matt Lewis <matthewwalkerlewis at gmail.com> Feb 17, 2005
• 456 views

Robert Craig wrote:
> 
> 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)...
> 
> 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.

I can confirm (for Win2k, at least) that using the constant after you've
already created a console works fine.  Interestingly, it even seems to
work after a call to free_console().

Matt Lewis

5. Re: Wierd error (PING ROB)

• Posted by Brian Broker <bkb at cnw.com> Feb 17, 2005
• 457 views
• Last edited Feb 18, 2005

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 don't trust you...
sizeofCSBI should be 22

I've got GetConsoleScreenBufferInfo wrapped in my Console lib.  The lib is 
still not done but it's useable.  If you'd like to take a look at it, let me
know...

-- Brian