SetFilePointer returns ERROR_NOACCESS....

[piotrus]

When I call SetFilePointer function I get ERROR_NOACCESS. :( What could be the reason?

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...
invoke SetFilePointer,hDebugFile,1,NULL,FILE_BEGIN
...


I open a file using CreateFile. It returns NO_ERROR.
I call ReadFile afterwards and also everything`s ok.

[P1]

Try this:

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invoke SetFilePointer, hErrorFile, 0, NULL, FILE_BEGIN

I am going to guess ( You have not supplied enough information to know. ), that this created file is empty and a move of 1 is ERROR_NOACCESS.

Welcome   :U

Regards, P1   :8)

[sebart7]

Each time when some API call failed and You arent sure why, You may get information about what hapened from system.
Put invoke GetLastError just after suspicious call and it will return ErrorDescription in EAX.
You may stop there (INT 3 or anything) to read whats in EAX then input returned value into ErrLook.exe,
It will show You error description in human readable form.
(You can find ErrLook.exe attached below in this post)

Code Select Expand


(...)
invoke SetFilePointer,hDebugFile,1,NULL,FILE_BEGIN
invoke GetLastError
int 3                                  ; here You enter debuger and check
                                       ; ErrorCode in EAX (it will tell You "why")



[attachment deleted by admin]

[P1]

Each time when some API call failed and You arent sure why

ERROR_NOACCESS = Error #998,  Invalid access to memory location.  This is from Win32 Error Codes of WIN32 API help file.

So I think he did already.

A+ for enthusiasm.   :U

Regards,  P1   :8)

[P1]

As a conditional quick and dirty debug technique, Try this:

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ifdef g_Debug
    invoke GetTimeFormat,NULL,NULL,addr l_StartTime,addr szTPstring, addr szTime, 10h
    invoke OutputDebugString, addr szTime
endif   
Then use Dbgview by SysInternals/M$ to check debug output.

Regards,  P1   :8)

[MichaelW]

I suspect that the problem is related to this statement from the SetFilePointer documentation:

"The file handle must be created with the GENERIC_READ or GENERIC_WRITE access right."