Invisible console cursor problem

[dedndave]

I am having trouble getting the cursor to disappear in a console app.
I am using the GetConsoleCursorInfo and SetConsoleCursorInfo functions.
The first thing I do is use the Get function to read the initial console cursor info structure.
The value returned in bVisible is 0 (false), even though the cursor is visible (should be true).
If I attempt to set bVisible to any value other than 0, I get error 57h (invalid parm).
I can happily set the dwSize variable to any value from 1 to 64h, so long as bVisible is 0.

On a related issue, I notice in windows.inc equates...

TRUE    equ     1
FALSE   equ     0

Am I missing something here? I always thought it should be...

FALSE   equ     0
TRUE    equ     not FALSE

The later will yield -1 (i.e. 0FFh for bytes, 0FFFFh for words, and 0FFFFFFFFh for dwords).

[dedndave]

OK - I tried everything I know - lol - that took all of 10 minutes

I tried writing to the VGA CRTC registers (we all know how that went).
I tried positioning the cursor off-screen - the OS adjusts the window.
These are the tricks we used in the old days to make the cursor disappear on stubborn display adapters.

Any help out there ?

[dedndave]

I remember one more trick - let me try it.....
Not easy under windows, but I may be able to set the foreground attribute to black
on some unused location of the screen and set the cursor there when not in use.

[Jimg]

Code Select Expand


   .nolist
    include \masm32\include\masm32rt.inc
                                 
.data?
    cci   CONSOLE_CURSOR_INFO <>
    chand dd ?
.code
program:

    invoke GetStdHandle,STD_OUTPUT_HANDLE
    mov chand,eax
    invoke GetConsoleCursorInfo,chand,addr cci
    inkey "Press any key to hide cursor"
    mov cci.bVisible,FALSE
    invoke SetConsoleCursorInfo,chand,addr cci
    inkey "Press any key to restore cursor"
    mov cci.bVisible,TRUE
    invoke SetConsoleCursorInfo,chand,addr cci
    inkey "Press any key to exit..."
    ret

end program


This works for me.  There may be some extraneous stuff in there, it's cut an paste from elsewhere.

[cobold]

dedndave,

does the following example work on your machine? On mine it worked fine.

Code Select Expand

include \masm32\include\masm32rt.inc

.data?
ConCurInfo  CONSOLE_CURSOR_INFO <?>
hStd        DWORD ?

.code
start:
    invoke GetStdHandle,STD_OUTPUT_HANDLE
    mov hStd,eax
    .if hStd==INVALID_HANDLE_VALUE
        print "Error GetStdHandle",13,10
        jmp _exit
    .endif
    invoke GetConsoleCursorInfo,hStd,ADDR ConCurInfo
    test eax,eax
    jz _exit
    print "dwSize: "
    print str$(ConCurInfo.dwSize),13,10
    print "bVisible: "
    print str$(ConCurInfo.bVisible),13,10
    print "now turning cursor off..."
    mov ConCurInfo.bVisible,FALSE
    invoke SetConsoleCursorInfo,hStd,ADDR ConCurInfo
    invoke Sleep,5000
    mov ConCurInfo.bVisible,TRUE
    invoke SetConsoleCursorInfo,hStd,ADDR ConCurInfo
_exit:
    exit
end start

[dedndave]

dang - both of those work - lol
i must be doing something wrong
maybe i was bad in a past life (been an angel in this one  ::) ) - lol

Thanks guys - i will let you know what i find

[dedndave]

lol - dang
my fault totally
i had been looking at the CONSOLE_SCREEN_BUFFER_INFO structure
all the variables are word size

CONSOLE_CURSOR_INFO is (for some odd reason) dwords
so - i was trying to set the high-order word of dwSize rather than bVisible
Thanks for the help guys