DeleteFile() Function Failure - C / C++ / MFC Discussion Boards

Re: my exe appears in task manager after closing.

Erudite_Eric7-Jul-13 23:33

7-Jul-13 23:33

Why did you replace CDialog::OnClose(); given you by the wizzard with PostQuitMessage()?

You HAVE to allow the base class to function correctly.

modified 9-Jul-13 6:18am.

First 10 or 20 lessons

C-P-User-34-Jul-13 13:02

C-P-User-3

4-Jul-13 13:02

Can someone point me to a site with the first ten or twenty lessons for newbee/refresher material for plain old regular C ?

The last course in C I had was years ago.

Oh, and in before first comment; yes, I know about google.

(That's why I'm asking here !)

Re: First 10 or 20 lessons

thanh_bkhn4-Jul-13 17:52

thanh_bkhn

4-Jul-13 17:52

I used Google, and I found some sites:
http://www.cprogramming.com[^]
http://www.learn-c.org/[^]
http://www.w3schools.in/c-programming-language/intro/[^]
I think you found these, too. But didn't they satisfy you yet?

"Never memorize something that you can look up." - Albert_Einstein

Re: First 10 or 20 lessons

Richard MacCutchan4-Jul-13 21:05

Richard MacCutchan

4-Jul-13 21:05

C-P-User-3 wrote:
yes, I know about google.

So what is wrong with some of these links[^]?

Use the best guess

Re: First 10 or 20 lessons

C-P-User-35-Jul-13 9:08

C-P-User-3

5-Jul-13 9:08

Here's what's "wrong" with them: they came from google.

Some time ago, google became the premier web search tool.

Some time after that, money came into play.

Some time after that, Newton's third law, in terms of psychodynamics and economics, produced the "Search Engine Optimization" (SEO) phenomenon.

Some time after that, the financial aspect of "finding the best" came into the procedure.

I don't understand all the inputs, but I have seen enough of the outputs to understand that the algorithm is now different from what it was several years ago.

Hence, asking the direct opinion of a bunch of guys on a site like this can produce a far more easily understood "search result" with the biases and prejudices far more easily inferred than a list that google produces. With those biases and prejudices more clearly evident and understood than an "automated" response, I can make a decision with which I'm far more comfortable.

I guess the concept parallels wikipedia these days; i.e.,

"...NPOV is absolute and non-negotiable..."

From what I've seen, the same thing that happened to wikipedia's "...NPOV..." closely approximates what has happened to google's algorithms.

All this is from guessing, based on the results I've personally observed.

So,,,,,,,,,,

That's why I like opinions from here better than from there.

Re: First 10 or 20 lessons

Richard MacCutchan5-Jul-13 22:13

Richard MacCutchan

5-Jul-13 22:13

C-P-User-3 wrote:
Here's what's "wrong" with them: they came from google.

And how do you think we find "the best", whatever that may mean. I learned C from Kernighan & Ritchie[^], which is, in my opinion, one of the best programming guides ever written. But then I may well have missed lots of others.

Use the best guess

Re: First 10 or 20 lessons

CPallini4-Jul-13 21:07

CPallini

4-Jul-13 21:07

K&R and programming.
Since you already know Google, a foundation book and experience is all other you need.

Veni, vidi, vici.

DeleteFile() Function Failure

Donguy19764-Jul-13 10:10

Donguy1976

4-Jul-13 10:10

Hey there

In my VC++ application i see that this function fails in certain times, but was not able to reproduce it.

So am trying to debug and have few questions.

Does the DeleteFile() fails if multiple files are deleted quickly inside a loop and if some files are larger in size?

What other possible causes can lead to DeleteFile() to fail?

Re: DeleteFile() Function Failure

thanh_bkhn4-Jul-13 17:46

thanh_bkhn

4-Jul-13 17:46

There are some reasons lead to DeleteFile() failure:
1. File not found
2. Path not found
3. Access denied
The first two reason maybe avoidable, but when you delete a large amount of file, depending on the disk status, there is a possibility that the access error happens. I also encountered this error when manually delete a directory which contains a large amount of files and sub directories, so I have to retry several times.
If you use DeleteFile() in your program, I think you should use catch and retry deleting several times before give it up.

"Never memorize something that you can look up." - Albert_Einstein

Re: DeleteFile() Function Failure

Richard MacCutchan4-Jul-13 21:02

Richard MacCutchan

4-Jul-13 21:02

Donguy1976 wrote:
What other possible causes can lead to DeleteFile() to fail?

If the call fails then you can find the reason by calling GetLastError(), as described in the documentation[^].

Use the best guess

Re: DeleteFile() Function Failure

hans.sch11-Jul-13 6:56

hans.sch

11-Jul-13 6:56

From the MSDN documentation of DeleteFile:

If the function fails, the return value is zero (0). To get extended error information, call GetLastError.

GetLastError returns an error code which you can convert into a string via the FormatMessage function. See http://msdn.microsoft.com/en-us/library/windows/desktop/ms680582%28v=vs.85%29.aspx[^] for an example. One possible reason might be that you are trying to delete the same file more than once.

Re: DeleteFile() Function Failure

Erudite_Eric15-Jul-13 2:30

Erudite_Eric

15-Jul-13 2:30

Donguy1976 wrote:
What other possible causes can lead to DeleteFile() to fail?

Well, the blindingly obvious are:

1) It doesnt exist.
2) Somthing else has it open.

The less obvious is that your calling code doesnrt have Delete authorisation.

Loo ak the error return, it will tell you all about it.

Class not registered error

sdancer754-Jul-13 2:30

sdancer75

4-Jul-13 2:30

Hi,

I created a source filter and is registered successfuly. Every time I use GraphEdit it works fine but when I try to use under MFC/C++ CoCreateInstance fails as not registered (error 0x80040154).

C++

hr = CoCreateInstance(CLSID_PIAsyncFile, NULL,CLSCTX_INPROC_SERVER, IID_IBaseFilter, (void **)&pAsync);

I tried again and again with regsvr32 and successfully registers the filter.

What seems to be wrong here?

I use 32Bit debug builds, on Win7 64bit system.

Regards,

sdancer75

Re: Class not registered error

«_Superman_»4-Jul-13 20:01

«_Superman_»

4-Jul-13 20:01

Make sure you've called CoInitialize or CoInitializeEx properly before calling CoCreateInstance.

«_Superman_»
I love work. It gives me something to do between weekends.

Microsoft MVP (Visual C++) (October 2009 - September 2013)

Polymorphism in C

Re: Class not registered error

sdancer754-Jul-13 21:34

sdancer75

4-Jul-13 21:34

Thanks,

I have called the

C++

HRESULT hr = CoInitializeEx(NULL, COINIT_APARTMENTTHREADED);

at the class construction and

C++

CoUninitialize();

at the destruction.

Any other filter is successfully CoCreateInstance except my filter.

sdancer75

Re: Class not registered error

«_Superman_»4-Jul-13 21:46

«_Superman_»

4-Jul-13 21:46

Get the error returned in hr and use the Error Lookup tool check what the error is.

«_Superman_»
I love work. It gives me something to do between weekends.

Microsoft MVP (Visual C++) (October 2009 - September 2013)

Polymorphism in C

Re: Class not registered error

sdancer754-Jul-13 22:53

sdancer75

4-Jul-13 22:53

Hi,

As you can see in question at the very begging, the error code is 0x80040154 which means "class is not registered"

This is strange since the class is indeed registered at sysWOW3264 (a mirror registry for 32-bit windows apps running on 64bit windows) since my source filter is 32-bit.

Under ms filter graph, I can find and use successfully the filter, but the problem still exists under my MFC project.

PS:In my stdafx.h I declare my filter as follows

C++

#include "INITGUID.H"

//{8576CEC8-964D-4B51-AC45-2B24DE748E23} My Async Source (File)
DEFINE_GUID(CLSID_PIAsyncFile,
			0x8576CEC8, 0x964D, 0x4B51, 0xAC, 0x45, 0x2B, 0x24, 0xDE, 074, 0x8E, 0x23);

Thanx

sdancer75

Re: Class not registered error

«_Superman_»4-Jul-13 23:00

«_Superman_»

4-Jul-13 23:00

Sorry, I didn't notice the error code you posted in your question.
I'm assuming that the MFC project is built as a 32-bit application.

One more thing you can try -
There are both 32-bit and 64-bit versions of regsvr32.exe available in %SystemRoot%\Windows\System32 and %Systemroot%\Windows\SysWOW64.
Try registering the component with either of the 2 and check if the MFC application is able to find it.

«_Superman_»
I love work. It gives me something to do between weekends.

Microsoft MVP (Visual C++) (October 2009 - September 2013)

Polymorphism in C

Re: Class not registered error

sdancer754-Jul-13 23:27

sdancer75

4-Jul-13 23:27

Thanks,

Yes I know and I already tried both versions of regsvr32 (32 & 64 Bit) but still does not work.

Regards,

sdancer75

Re: Class not registered error

«_Superman_»4-Jul-13 23:41

«_Superman_»

4-Jul-13 23:41

All I can think of is that the COM component uses some dependency files like DLLs that GraphEdit is able to find but the MFC application is not.
Does the COM component reside is some folder along with other dependency files.
If so, you can either try to copy the EXE to that folder or change the working directory using the SetCurrentDirectory API.

«_Superman_»
I love work. It gives me something to do between weekends.

Microsoft MVP (Visual C++) (October 2009 - September 2013)

Polymorphism in C

Re: Class not registered error

sdancer754-Jul-13 23:57

sdancer75

4-Jul-13 23:57

I am not sure about that.... The filter resides is a local folder and not in windows subfolder and is a "debug build". I will try to move the filter inside the C:\windows\SysWOW64 and register again.

sdancer75

Re: Class not registered error

sdancer755-Jul-13 0:13

sdancer75

5-Jul-13 0:13