Re: Internal buffer of file - C / C++ / MFC Discussion Boards

Re: Internal buffer of file

David Crow10-Aug-09 2:44

David Crow

10-Aug-09 2:44

Cedric Moonen wrote:
But what does notepad have to do here ?

Nothing. You mentioned it first (as an example), and the OP just concurred.

"Old age is like a bank account. You withdraw later in life what you have deposited along the way." - Unknown

"Fireproof doesn't mean the fire will never come. It means when the fire comes that you will be able to withstand it." - Michael Simmons

Re: Internal buffer of file

Cedric Moonen10-Aug-09 2:48

Cedric Moonen

10-Aug-09 2:48

He was talking about a program in which he was writing the text file and saving it. Notepad was just an example but I don't know what this program (being notepad or whatever else) has something to do with the question...

Cédric Moonen
Software developer

Charting control [v2.0]
OpenGL game tutorial in C++

Re: Internal buffer of file

Randor 10-Aug-09 7:38

Randor

10-Aug-09 7:38

Hello trioum,

When an application is modifying disk clusters at a very high speed... the NT Cache Manager could buffer these disk changes to avoid thrashing the drive. You can call the FlushFileBuffers Function[^] and flush the buffers associated with the handle. Another option is to open the file with FILE_FLAG_WRITE_THROUGH and FILE_FLAG_NO_BUFFERING to ask the cache manager to disable buffering.

INFO: FILE_FLAG_WRITE_THROUGH and FILE_FLAG_NO_BUFFERING[^]

You should be aware that these CreateFile flags can have an enormous negative impact on disk performance.

Best Wishes,
-David Delaune

Re: Internal buffer of file

trioum10-Aug-09 20:09

trioum

10-Aug-09 20:09

I cannot use flushfilebuffer function because it is already opened for write access by third party software. I can only read it

Trioum

Re: Internal buffer of file

Randor 10-Aug-09 23:33

Randor

10-Aug-09 23:33

trioum wrote:
I cannot use flushfilebuffer function because it is already opened for write access by third party software.

Sure you can. Smile | :)

Here is a little professional tip that Mark Russinovich used to create his Sync v2.0[^] disk flusher.

BOOL FlushDiskDrive(TCHAR *szDrive)
{
	BOOL bRet = FALSE;
	HANDLE h = CreateFile(szDrive, GENERIC_READ|GENERIC_WRITE, FILE_SHARE_READ|FILE_SHARE_WRITE,NULL,OPEN_EXISTING,0,NULL);
	if(INVALID_HANDLE_VALUE != h)
	{
		bRet = FlushFileBuffers(h);
		CloseHandle(h);
	}
	return bRet;
}
//Usage:
FlushDiskDrive(_T("\\\\.\\\\C:));

What we are doing here is opening the disk volume and flushing the entire volume cache. This code will not work for removable USB drives. This code also requires Administrator privileges. It is possible that a standard user with the FILE_FLAG_BACKUP_SEMANTICS permission may be able to use it, I am not certain and do not have time to test... I am leaving the office in a few minutes.

Let me know if this works for you.

Best Wishes,
-David Delaune

Re: Internal buffer of file

trioum11-Aug-09 0:14

trioum

11-Aug-09 0:14

Thanks for I will R&D and let you know

Trioum

Re: Internal buffer of file

trioum11-Aug-09 20:33

trioum

11-Aug-09 20:33

No it is not working as I want . What I do I open a note pad in c drive and type something . and the run your code by specifying "c" drive .code run successfully but data in notepad not saved .according to you data in notepad must be saved???.

Trioum

Re: Internal buffer of file

Randor 11-Aug-09 21:23

Randor

11-Aug-09 21:23

You lost me here. Why are we suddenly talking about notepad? Based on prior thread posts I thought you had problems flushing an XML file from a third-party software.

trioum wrote:
but data in notepad not saved .according to you data in notepad must be saved???.

What are you asking here? Are you actually asking me why text in notepad memory is not being saved to disk when you flush the mounted volume? Sigh | :sigh:

Unfortunately I do not think we are on the same level here.

Good Luck,
-David Delaune

Re: Internal buffer of file

trioum12-Aug-09 0:18

trioum

12-Aug-09 0:18

I first check with xml file is it not working then with text file . in both it is not working

Trioum

E_NOINTERFACE returned while using SHEmptyRecycleBin

anjali_saluja9-Aug-09 23:09

anjali_saluja

9-Aug-09 23:09

Hello.

I am using ::SHEmptyRecycleBin(NULL, NULL, SHERB_NOCONFIRMATION|SHERB_NOPROGRESSUI|SHERB_NOSOUND);

to empty recycle bin in a utility that checks the various aspects of a PC like if antivirus is installed or not, firewall enabled or not etc. To empty recycle bin I use the above call. I have included "shellapi.h" and that's all.

Am I missing something? I thought this is all I need to do. I am using VS2005.

Regards.

Re: E_NOINTERFACE returned while using SHEmptyRecycleBin

Chandrasekharan P9-Aug-09 23:25

Chandrasekharan P

9-Aug-09 23:25

I think yes.. if you wnat more information check the link[^]

Re: E_NOINTERFACE returned while using SHEmptyRecycleBin

anjali_saluja10-Aug-09 3:30

anjali_saluja

10-Aug-09 3:30

Could not really see where I made a mistake. Reading that article - well, I did that before I posted here. But still I reread it. Frown | :(

Still lost.

Regards.

Re: E_NOINTERFACE returned while using SHEmptyRecycleBin

Adam Roderick J10-Aug-09 2:30

Adam Roderick J

10-Aug-09 2:30

What is real issue?

Величие не Бога может быть недооценена.

Re: E_NOINTERFACE returned while using SHEmptyRecycleBin

anjali_saluja10-Aug-09 3:31

anjali_saluja

10-Aug-09 3:31

Getting a return value of E_NOINTERFACE when I was expecting S_OK. Smile | :)

I know, I made a mistake. Now where is it? That's the question I am trying to solve.

Regards.

error C2520: conversion from unsigned __int64 to double not implemented, use signed __int64

V K 29-Aug-09 22:41

V K 2

9-Aug-09 22:41

Hi,
My code is as below
MEMORYSTATUSEX msex;
GlobalMemoryStatusEx(&msex);
DWORD dwBytesPerMB = 1024 * 1024;
m_RAM = (float)msex.ullTotalPhys / (float)dwBytesPerMB;

m_RAM = (float) ( m_RAM * 1.01 ); (Getting compilation error at this point)

Can I know how to fix this..

Thanks...

Re: error C2520: conversion from unsigned __int64 to double not implemented, use signed __int64

Cedric Moonen9-Aug-09 23:53

Cedric Moonen

9-Aug-09 23:53

It would help a lot if you could tell us the types of the different variables that you are using in your code snippet.
On the other hand, did you try what the compiler suggested you: using a signed __int64 instead of an unsigned __int64 ?

Cédric Moonen
Software developer

Charting control [v2.0]
OpenGL game tutorial in C++

Re: error C2520: conversion from unsigned __int64 to double not implemented, use signed __int64

Stuart Dootson10-Aug-09 0:17

Stuart Dootson

10-Aug-09 0:17

The implication from the error message you've posted is that m_RAM has type unsigned __int64 (it'll try to convert it to double when you multiply by 1.01).

You could either a) change the type of m_RAM to signed __int64 (as indicated by the error message), or b) alter the expression causing the error. How about:

m_RAM = m_RAM + (m_RAM / 100);

?

That might not give exactly the same result, but it'll probably be close enough!

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

Re: error C2520: conversion from unsigned __int64 to double not implemented, use signed __int64

Michael Schubert10-Aug-09 3:55

Michael Schubert

10-Aug-09 3:55

You can remedy this by applying the processor pack for VC6 (I'm assuming that you're using VC6):
http://msdn.microsoft.com/en-us/vstudio/aa718349.aspx[^]

Timestamp of RTP header?

Souldrift9-Aug-09 21:51

Souldrift

9-Aug-09 21:51

Good morning Smile | :)

,

brief question. Has anybody experience with RTP?
I got an RTP engine working already but don´t know how exactly the timestamp property is set in the RTP header. Usually an RTP header is 12 byte long with bytes 3-7 being the timestamp. But how exactly is the timestamp (system time?) stored in these 4 bytes? Is there a certain specification about it? Or totally up to me? Like the accuracy of time and little or big endian?

Thanks.

Souldrift

Re: Timestamp of RTP header?

Stuart Dootson10-Aug-09 0:24

Stuart Dootson

10-Aug-09 0:24

Looking at the spec[^], it seems to me that the timestamp format is left to be defined by your application.

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

How to build .mc file

Aabid9-Aug-09 20:42

Aabid

9-Aug-09 20:42

Hello All

I have a file as "Sample.mc" copied from the below link.....

http://msdn.microsoft.com/en-us/library/bb540476(VS.85).aspx[^]

These r some rules mentioned on the above page how to build this file,
Build the message DLL from Sample.mc using the following steps:

1. mc -U sample.mc
2. rc -r sample.rc
3. link -dll -noentry -out:sample.dll sample.res

but i want to know where and how to apply these rules...
i am using Vs 2005 VC++(Win32 API)....

Any suggestion is highly appreciated

Thanks

Re: How to build .mc file

Garth J Lancaster9-Aug-09 21:34

Garth J Lancaster

9-Aug-09 21:34

see if this helps (a quick search here on CP would have found it ....)

Using MC.exe, message resources and the NT event log in your own projects[^]

'g'

Re: How to build .mc file

Aabid9-Aug-09 23:49

Aabid

9-Aug-09 23:49

Thanks Garth J Lancaster!!!
it was a great article. I got my work Done ...
Thanks

Message Hook in OCX causes IME issue

Nishad S9-Aug-09 20:22

Nishad S

9-Aug-09 20:22

For supporting Tab key navigation through controls in the popup dialog created in an OCX, I have implemented the message hook as described in Microsoft Help and Support Article ID: 187988[^]

Now the IME for Japanese is not working fine. When the IME is enabled for input as Hiragana (or something), there is no proper result. I found that this is because the keyboard message is always altered in the hook procedure.

Do anybody have come such a scenario and found a solution?

Thank you.

- ns ami -

CEditBox Validation

shiv@nand9-Aug-09 20:02

shiv@nand

9-Aug-09 20:02

I want to Validate a EditBox only number entry, including (+ or - values).I used SpanIncluding function of CString. my code is
CString value;
value=m_strEditBox.SpanIncluding ("0123456789-+");

if(!(value==m_strEditBox && value.GetLength ()==m_strEditBox.GetLength ()))
{
MessageBox(_T("Invalid Entry"),MB_OK,MB_ICONINFORMATION);

return;
}
it works fine only when user enters like -10 or +15.

But if user enters wrong value like 10- or -14- or +15-20 or ----- or +++++ for this type of values entry ,the above condition will not work it will not fire the error Message like Invalid Entry.For this i am getting strange output so how to restrict or validate for this type of entry in EditBox.Help me. Thanks in Advance.

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.