Writing File

[SuCkEr]

hi all

i create a small app just for a test i don't why he got a crashes when write to file

.data
FILENAME DB "key.lic",0.data?
hInstance	HINSTANCE	?  
read	db  ?
write   db  ?.const
IDD_DLG1 equ 1000
IDC_BTN1 equ 1001
IDC_EDT1 equ 1002DlgProc proc hWnd:HWND, uMsg:UINT, wParam:WPARAM, lParam:LPARAM 
.if uMsg == WM_INITDIALOG
	invoke	SendMessage, hWnd, WM_SETICON, 1, eax	
	.elseif uMsg == WM_COMMAND
	mov	eax,wParam
	.if eax==IDC_BTN1
	invoke CreateFile,ADDR FILENAME,GENERIC_READ+GENERIC_WRITE,0,NULL,CREATE_NEW,FILE_ATTRIBUTE_NORMAL,NULL
	invoke GetDlgItemText,1000,1002,addr read,512
	invoke SetFilePointer,addr FILENAME,0,0,FILE_BEGIN
	invoke WriteFile,addr FILENAME,addr read,32,32,NULL
	POP EAX
	invoke CloseHandle, eax
	.elseif	uMsg == WM_CLOSE
	invoke	EndDialog, hWnd, 0
	invoke ExitProcess,0
	.endif
.endif
		xor eax,eax
	Ret
DlgProc EndP
end start

is there any suggest or advice?

[starzboy]

hello ...

since its a single line work ... i suggest u do this :

.data?

hdir db 256 dup(?)

htemp dd ?

invoke GetDlgItemText,hWnd,IDC_EDT1,addr read,512 ; Copy value from Editbox to buffer [read]

invoke GetCurrentDirectory,sizeof hdir ,addr hdir ; Get Current Directory

invoke lstrcat,addr hdir,offset FILENAME

invoke CreateFile,addr hdir,GENERIC_WRITE,0,0,CREATE_ALWAYS,FILE_ATTRIBUTE_NORMAL,0 ; File Attributes

push eax

invoke WriteFile,eax,addr read,sizeof read,addr htemp,0 ; WrireFile

pop eax

invoke CloseHandle,eax ; CloseHandle

[Ox87k]

i think the error is here:

invoke WriteFile,addr FILENAME,addr read,32,32,NULL

maybe it would be:

dwBytesWritten dw 0

invoke lstrlen, addr read

invoke WriteFile, addr FILENAME, addr read, eax, addr dwBytesWritten, NULL

:-|

[sEby]

first mistake is here:

invoke GetDlgItemText,1000,1002,addr read,512

and sould be:

invoke GetDlgItemText,hWnd,1002,addr read,512

second

invoke SetFilePointer,addr FILENAME,0,0,FILE_BEGIN

from win32api help file

The SetFilePointer function moves the file pointer of an open file. DWORD SetFilePointer(	HANDLE hFile,	// handle of file 
	LONG lDistanceToMove,	// number of bytes to move file pointer 
	PLONG lpDistanceToMoveHigh,	// address of high-order word of distance to move  
	DWORD dwMoveMethod 	// how to move 
   );	
ParametershFileIdentifies the file whose file pointer is to be moved. The file handle must have been created with GENERIC_READ or GENERIC_WRITE access to the file. lDistanceToMoveSpecifies the number of bytes to move the file pointer. A positive value moves the pointer forward in the file and a negative value moves it backward. lpDistanceToMoveHighPoints to the high-order word of the 64-bit distance to move. If the value of this parameter is NULL, SetFilePointer can operate only on files whose maximum size is 2^32 - 2. If this parameter is specified, the maximum file size is 2^64 - 2. This parameter also receives the high-order word of the new value of the file pointer. dwMoveMethodSpecifies the starting point for the file pointer move. This parameter can be one of the following values: Value	Meaning
FILE_BEGIN	The starting point is zero or the beginning of the file. If FILE_BEGIN is specified, DistanceToMove is interpreted as an unsigned location for the new file pointer.
FILE_CURRENT	The current value of the file pointer is the starting point.
FILE_END	The current end-of-file position is the starting point.

third:

invoke WriteFile,addr FILENAME,addr read,32,32,NULL

from the same document ...

The WriteFile function writes data to a file and is designed for both synchronous and asynchronous operation. The function starts writing data to the file at the position indicated by the file pointer. After the write operation has been completed, the file pointer is adjusted by the number of bytes actually written, except when the file is opened with FILE_FLAG_OVERLAPPED. If the file handle was created for overlapped input and output (I/O), the application must adjust the position of the file pointer after the write operation is finished. BOOL WriteFile(	HANDLE hFile,	// handle to file to write to 
	LPCVOID lpBuffer,	// pointer to data to write to file 
	DWORD nNumberOfBytesToWrite,	// number of bytes to write 
	LPDWORD lpNumberOfBytesWritten,	// pointer to number of bytes written 
	LPOVERLAPPED lpOverlapped 	// pointer to structure needed for overlapped I/O
   );	
ParametershFile
......

the rest findit .....

Edited December 15, 2006 by seby