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That returns a HBITMAP.

The following pseudocode is naiive, but should work.

;Get pointer to raw data, and its size
invoke GlobalLock, hClipboard
mov pData,eax
invoke GlobalSize,pData
mov dLen,eax

;Open a new/existing file for writing
invoke CreateFile,pstrName,GENERIC_WRITE,FILE_SHARE_READ,NULL,CREATE_ALWAYS,FILE_ATTRIBUTE_NORMAL,NULL
mov hFile,eax

;Write all the data
.while dLen>0
  mov dWrote,0
  invoke WriteFile,hFile,pData,dLen,addr dWrote,NULL
  mov eax,dWrote
  sub dLen,eax
  add pData,eax
.endw

;Dont forget to unlock the data
invoke GlobalUnlock,hClipboard

Just provide a suitable pathname for the file eg "TESTFILE.BMP"
Note that you should make sure that OpenClipboard succeeded before proceeding!

I'm pretty sure you are writing a trojan / rat based on the sum total of your posts since you joined this forum, which is against The Rules of this forum, however I will overlook your intent until you clearly cross the line.
Just be aware that we will not tolerate malcode, or malcoders here.
There are more suitable forums for those kinds of topics.

Ok I tried this, but GlobalLock wouldn't write the first block of the memory. Rather it fails returning NULL. Pls can you tell me what's the problem is?

Thanks,

C K

Thanks Homer,

The last error was ERROR_INVALID_HANDLE, All the ClipBoard Functions returned true. GetClipBoardData returns the handle to the clipboard object.

It's with GlobalLock not returning the first memory block. Please can you help me out

Thanks,

C K

Humm, I never tried this on the desktop window (NULL) before.
Try calling GetDesktopWindow and pass that handle instead of NULL (HWND_DESKTOP).
Maybe it will help?

Try this:

invoke keybd_event, VK_SNAPSHOT, 0, 0, 0
invoke keybd_event, VK_SNAPSHOT, 0, KEYEVENTF_KEYUP, 0


Here we are not only simulating the KEYDOWN, but also simulating KEYUP.
Maybe it will help.

Its also worth knowing that I saw something about Active window in regards to input params for this call.

And if that does not help, you will need to use a different method to screencapture - this is not the only way.

IIRC then

invoke GetClipboardData, CF_BITMAP
mov hClipboard,eax

does not return the handle of the clipboard _but_ the handle of the bitmap and you don't even need to call GlobalLock at all.

Try saving it using Donkey's proc here: http://www.asmcommunity.net/board/index.php?topic=17752.msg137060#msg137060

Hope that works.

check your OpenClipBoard call returned TRUE, under some circumstances it can fail (if its open in another process for example)
if it returns FALSE you can't do anything

You never closehandle(hFile) anywhere in the program. try doing that after the writefile call

I found that if I run the app from windows Folder Explorer shell, it doesnt work, but if I run it from QEditor (ShellExecute) then it works.
I believe the cause is , as mentioned, that OpenClipboard will fail if another process (such as the Folder shell) is already using it... you'll need to repeatedly try it in a loop until it succeeds, with a small Sleep in there, or something.

Called the EXE from a separate code, that did the trick. Each time it works perfectly, still no answer as to why GetClipboardData is not fetching that data despite OpenClipboard and keybd_event returning appropriate results, any idea ?

invoke keybd_event, VK_SNAPSHOT, 0, 0, 0
invoke ShellExecute, NULL, ADDR lpOperation, ADDR lpFile, NULL, NULL, SW_HIDE

Thanks All  :)