C / C++ / MFC

Re: EnterCriticalSection() problem on Vista

13-Jul-08 18:52

Thanks. This is much helpful.

SRKSHOME17-Jul-08 3:15

Re: EnterCriticalSection() problem on Vista

17-Jul-08 3:15

Hi...
I have checked it again. I don’t think there is any deadlock present. There is no resource as such on which more than 1 threads are waiting.

LockCount - RecursionCount = Number of waiting threads

In my case, Number of waiting threads = 0.

But I found one more interesting thing on vista. WaitForSingleObject() is used here. When I called this function with TIMEOUT=INFINITE. It is not coming out of loop at all. It will be looping there. On Vista WaitForSingleObject() returns 258(I guess it is=WAIT_TIMEOUT). But on XP and lower versions of OS this function returns 0(I guess it is=WAIT_OBJECT_0) and come out of the of the loop.Please see the below code.

bool DSEventSemaphore::WaitForSignal( DWORD TimeOut ) //TimeOut=INFINITE

{
if( State == SemInvalid )
{
return false;
}
DWORD retval;

#ifndef DSTRACEABLE_SIGNAL_STACK /*I haven't defined it. So it wiil not execute.*/
retval = WaitForSingleObject( event, TimeOut );

#else //It will come here
do
{ retval = WaitForSingleObject( event, (TimeOut< DSSLEEP_PERIOD ? TimeOut : DSSLEEP_PERIOD) ); //DSSLEEP_PERIOD=500
if( retval == WAIT_TIMEOUT )
{
if( TimeOut < DSSLEEP_PERIOD )
{
TimeOut = 0;
}
else
if( TimeOut != INFINITE )
{
TimeOut -= DSSLEEP_PERIOD;
}
}
else
{
TimeOut = 0;
}

} while( TimeOut );

#endif

switch (retval)
{
case WAIT_OBJECT_0:
State = SemOK;
return true;

case WAIT_TIMEOUT:
State = SemTimeOut;
Error = GetLastError();
return false;

case WAIT_FAILED:
default:
Error = GetLastError();
State = SemSystemError;
return false;
}
}

Could you please help me.

Joe Woodbury17-Jul-08 5:45

Joe Woodbury

17-Jul-08 5:45

I hate to say this, but you have me stumped. Have you verified this on another Vista install? Is your software running in a separate user account? (Like, as a service.) You could write a small program with two threads that does nothing but waits using various mechanisms.

Anyone who thinks he has a better idea of what's good for people than people do is a swine.
- P.J. O'Rourke

VC ++ help

paresh_sarjani11-Jul-08 3:31

paresh_sarjani

11-Jul-08 3:31

i hav two projects made in VC 6 and i want to combine them into a single application

it may hav common variables or structures

bt they should be made global

can ne1 help?

Re: VC ++ help

Cedric Moonen11-Jul-08 3:56

Cedric Moonen

11-Jul-08 3:56

There's no magic way for doing that: you'll have to copy and paste part of the code you want to reuse in your new application. That's probably not an easy task...

Cédric Moonen
Software developer

Charting control [v1.4]
OpenGL game tutorial in C++

Re: VC ++ help

sudhir_Kumar11-Jul-08 19:53

sudhir_Kumar

11-Jul-08 19:53

TRUE

-@SuDhIrKuMaR@-

how data is managed in CString class?

nisha0000011-Jul-08 3:12

nisha00000

11-Jul-08 3:12

Regards

Nisha

Re: how data is managed in CString class?

Mark Salsbery11-Jul-08 5:38

Mark Salsbery

11-Jul-08 5:38

You have the source code - use it! Smile | :)

I guarantee the info you find there will be more (or at least as) accurate than any response here.

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

TryEnterCriticalSection() problem

SRKSHOME11-Jul-08 2:42

11-Jul-08 2:42

When I use TryEnterCriticalSection() I am getting an error as TryEnterCriticalSection' : undeclared identifier. I have included #define _WIN32_WINNT 0x0500 and windows.h in my header file. How can solve this problem?
Thanks in advance.

CPallini11-Jul-08 2:48

11-Jul-08 2:48

Possibly you need an updated Platform SDK.
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

SRKSHOME11-Jul-08 2:54

11-Jul-08 2:54

I tried this on Windows XP and Vista as well.

CPallini11-Jul-08 2:57

11-Jul-08 2:57

My point wasn't about the OS it was about the installed SDK. As the name implies, the SDK is a development tool, it doesn't come together with the OS, you need to download it from the Microsoft website.

SRKSHOME14-Jul-08 2:06

14-Jul-08 2:06

Thanks. I am able to compile it without any error now. I have incuded the definition _WIN32_WINNT=0x0502 in project settings instead of in the header file.

list box problem

sanjayvenkat11-Jul-08 2:19

sanjayvenkat

11-Jul-08 2:19

i need my list box to show the strings i add to it at runtime onebyone but the strings get listed finally after all operations are completed(all together)
what should be done for it??should any method be called after addstring method is called

Re: list box problem

CPallini11-Jul-08 2:32

11-Jul-08 2:32

You may call UpdateWindow on your listbox.

Re: list box problem

David Crow11-Jul-08 2:53

David Crow

11-Jul-08 2:53

sanjayvenkat wrote:
what should be done for it??

You should employ a worker thread so that the primary thread can keep the UI updated.

"Love people and use things, not love things and use people." - Unknown

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

Word frequency

flowingsun11-Jul-08 2:17

flowingsun

11-Jul-08 2:17

how many times a word is used in a sentence,or its frequency
eg:
“this is a dog and that is a pig”
result:
“is”:2
“and”:1
th:2
is:3
i:4
thank you!

Re: Word frequency

CPallini11-Jul-08 2:19

Convert CString to int or float

11-Jul-08 2:19

How much money are you ready to invest in?
Big Grin | :-D

i.e. 'Please provide code' is not the best way to go on. Read posting guidelines.

Re: Word frequency

_AnsHUMAN_ 11-Jul-08 2:25

_AnsHUMAN_

11-Jul-08 2:25

flowingsun wrote:
how many times a word is used in a sentence,or its frequency
eg:
“this is a dog and that is a pig”

Your question

flowingsun wrote:
result:
“is”:2
“and”:1
th:2
is:3
i:4

You already know the answer. Very Smart!!!

Somethings seem HARD to do, until we know how to do them.
Wink | ;-)

_AnShUmAn_

Re: Word frequency

Michael Schubert11-Jul-08 2:38

Michael Schubert

11-Jul-08 2:38

flowingsun wrote:
thank you!

You're welcome!

Trupti Mehta11-Jul-08 2:06

Trupti Mehta

11-Jul-08 2:06

In Evc++4, I want to convert CString to int/float. I use the following code :

// CONVERT STRING TO INT
CString csValue;
GetDlgItem(IDC_OpNo_EDIT)->GetWindowText( csValue );
m_opNo = atoi((char*)(LPCTSTR)csValue);

The above code works, but only with the first digit, so If I enter 34, I only get 3 in m_opNo int. same happens with float atof.

Can anyone tell what changes ae required to get full digit from CString to int. Is I enter 34 I want 34 as int.

Thanks

Terry

CPallini11-Jul-08 2:18

11-Jul-08 2:18

int i = _ttoi(csValue);

double f = _tstof(csValue);

Trupti Mehta12-Jul-08 0:38

Trupti Mehta

12-Jul-08 0:38

Thanks CPallini & everybody else.
This solved my problem for int's but not for float as _ttof or _tstof id not defined in tchar also. I am using eVc++4.0 with WinCE 5. I can't find the functions in eVC help or tchar.h file also & it throws compilation error :

error C2065: '_tstof' : undeclared identifier

Any other alternative to do the above task would be great.

Thanks

Terry

CPallini12-Jul-08 2:40

12-Jul-08 2:40

Well you can rool your own version:

#ifdef _UNICODE
#define _tstof wtof
#else
#define _tstof atof
#endif