C / C++ / MFC Discussion Boards

Re: Templates... they are nasty!!

Stuart Dootson3-Sep-09 23:37

Stuart Dootson

3-Sep-09 23:37

o.kauert wrote:
But it makes no sense to me as the compiler should only generate code that is USED.

VC++ has historically had issues with instantiating more than it necessarily needed with templates.

o.kauert wrote:
Err, what you are doing here is an OBVIOUS recursion that could not even be executed without stack overflow

Yes it could be executed. The condition within split (if (result != 0)) will terminate recursion at run-time. However, the compiler cannot reliably and economically perform the static analysis required to see that and know that the first call to split from clear will terminate the recursion, meaning it doesn't need an instantiation of clear to be called at that point.

o.kauert wrote:
What it's really about is code generation that does take place although the generated code is not actually needed. I will certainly never ever use a Array<Array<Array<Array<Array<Array<Array<Array<ArrayElement>...> container ANYWHERE So why does the compiler think I will?

Because it's unable to see as far as you - it doesn't have the knowledge of your design intent. It has to follow pre-defined rules about what to instantiate.

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

Re: Templates... they are nasty!!

o.kauert4-Sep-09 0:54

o.kauert

4-Sep-09 0:54

Stuart Dootson wrote:
o.kauert wrote:
What it's really about is code generation that does take place although the generated code is not actually needed. I will certainly never ever use a Array<array<array<array<array<array<array<array<arrayelement>...> container ANYWHERE So why does the compiler think I will?

Because it's unable to see as far as you - it doesn't have the knowledge of your design intent. It has to follow pre-defined rules about what to instantiate.

Sure, I agree with you and I know that the compiler behaves rule based all the time. But the implemented rule set of the MS compiler seems to not match the sensible reality in this case and as one can see the compiler does not even notice that there is an unresolvable issue for the way it operates here.
This COULD be solved however I think - given another compiler Wink | ;)

I will soon try GCC and see what happens.

Re: Templates... they are nasty!!

Stuart Dootson4-Sep-09 1:00

Stuart Dootson

4-Sep-09 1:00

o.kauert wrote:
I will soon try GCC and see what happens.

Oh, your code compiles fine with gcc. I tried that pretty much first, as I suspected a VC++-specific issue.

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

Re: Templates... they are nasty!!

o.kauert4-Sep-09 1:40

o.kauert

4-Sep-09 1:40

Stuart Dootson wrote:
Oh, your code compiles fine with gcc. I tried that pretty much first, as I suspected a VC++-specific issue.

That's good Smile | :)

So maybe I should start my next question... How can I REPLACE the VC++ compiler with the gcc counterparts within the VS IDE? I want to fully use the gcc toolchain and not the MS compiler, linker etc.

So is it possible to fully replace the tools and still get errors, warnings etc. in the VS IDE ( the message text is of course then coming from the gcc counterparts)? Also debugging should still be possible in the VS IDE. This would be really great! Any hints? Thanks Smile | :)

Re: Templates... they are nasty!!

Stuart Dootson4-Sep-09 1:52

Stuart Dootson

4-Sep-09 1:52

That's not so do-able Smile | :)

The VS IDE wouldn't correctly parse errors coming out of gcc, as they're different formats, and also the gcc debug format is completely different than the VC++ one - neither WInDbg nor Visual Studio can debug code produced by gcc. Also, I don't think you can build against MS libraries like MFC and ATL with gcc.

Alternatives? Eclipse CDT[^] and Dev-C++[^] are both IDEs using gcc. Also, I believe the Intel C++ compiler can be used as a drop-in replacement for MSVC, but that costs money Frown | :-(

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

PlaySound(MAKEINTRESOURCE, IDR_WAVE_RANDOM... problem

lctrncs3-Sep-09 7:08

lctrncs

3-Sep-09 7:08

The need to compile wav files into a Doc/View plus modeless dialog MFC program led to abandoning a functioning mechanism to play random wav files:

PlaySound("m_sStrConcatenatedStringWithPath",NULL,SND_FILENAME|SND_SYNC);

(where sStrConcatenatedStringWithPath = “/path/201.wav” etc.)

and adopting:

LPTSTR pRandomSound = m_sStrConcatenatedStringResource.GetBuffer(0);

PlaySound(MAKEINTRESOURCE, pRandomSound, GetModuleHandle(NULL), SND_SYNC|SND_RESOURCE);

m_sStrConcatenatedStringResource.ReleaseBuffer(0);

(where m_sStrConcatenatedStringResource = “IDR_WAVE_201” etc.).

...that fails to play the wav files even when...

PlaySound(MAKEINTRESOURCE, IDR_WAVE_201, GetModuleHandle(NULL), SND_SYNC|SND_RESOURCE);

will play the IDR_WAVE_201 resource.

Many attempts experimenting different ways to cast the CString to the LPTSTR and obtaining the handle to the executable led to the code above, which still will not play the random sound resource.

Suggestions?

"For a successful technology, reality must take precedence over public relations, for nature cannot be fooled." Richard Feynman, Minority Report to the Official Report on the Space Shuttle Challenger Crash

Re: PlaySound(MAKEINTRESOURCE, IDR_WAVE_RANDOM... problem

David Crow3-Sep-09 7:18

David Crow

3-Sep-09 7:18

lctrncs wrote:
PlaySound(MAKEINTRESOURCE, pRandomSound, GetModuleHandle(NULL), SND_SYNC|SND_RESOURCE);

What PlaySound() are you using that takes four arguments?

"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: PlaySound(MAKEINTRESOURCE, IDR_WAVE_RANDOM... problem

lctrncs3-Sep-09 12:27

lctrncs

3-Sep-09 12:27

Thank you for responding.

BOOL PlaySound(
LPCSTR pszSound,
HMODULE fdwSound,
DWORD fdwSound)

There are two arguments:

LPCSTR (pszSound) and HMODULE (fdwSound)
pRandomSound and GetModuleHandle(NULL)

and two flags:

DWORD fdwSound
SND_SYNC|SND_RESOURCE

Thanks again. I hope this answers your question.

Re: PlaySound(MAKEINTRESOURCE, IDR_WAVE_RANDOM... problem

David Crow3-Sep-09 18:15

David Crow

3-Sep-09 18:15

lctrncs wrote:
BOOL PlaySound(
LPCSTR pszSound,
HMODULE fdwSound,
DWORD fdwSound)

There are two arguments:

LPCSTR (pszSound) and HMODULE (fdwSound)
pRandomSound and GetModuleHandle(NULL)

and two flags:

DWORD fdwSound
SND_SYNC|SND_RESOURCE

You seem to be confused. Look at the code snippet in your original post. You are passing PlaySound() four arguments: 1) MAKEINTRESOURCE, 2) pRandomSound, 3) GetModuleHandle(NULL), and 4) SND_SYNC|SND_RESOURCE.

So my question still remains: where does this four-argument function come from? The answer to this may end up having no bearing on the actual problem, but if you can't post a working code snippet, it's kind of hard to come up with a useful answer.

Re: PlaySound(MAKEINTRESOURCE, IDR_WAVE_RANDOM... problem

lctrncs3-Sep-09 19:09

lctrncs

3-Sep-09 19:09

The

BOOL PlaySound(
LPCSTR pszSound,
HMODULE fdwSound,
DWORD fdwSound)

comes from the "Multimedia: Platform SDK" section of the Visual C++ 6.0 MSDEV documentation.

This specific use of the MAKEINTRESOURCE macro is documented in the "Technical Articles" section of the Visual C++ 6.0 MSDEV documentation in a file called "Moving Your Game to Windows, Part III.

Does this answer you question?

Re: PlaySound(MAKEINTRESOURCE, IDR_WAVE_RANDOM... problem

iraclyKv3-Sep-09 22:58

iraclyKv

3-Sep-09 22:58

When You add WAV resource by ID there is no way to call PlaySound (and other resource functions) by resource name and vice versa - when you add resource with resource name string - You can not access resource by it' ID.

For this resource script file:

//Resources.h
#define SOUND_1

//MyApp.rc
...
SOUND_1  WAV "snd1.wav"
"MOO"    WAV "moo.wav"

Valid PlaySound call is:

PlaySound(MAKEINTRESOURCE(SOUND_1), ...);
PlaySound("MOO", ...);

More Detailed Information About the Problem Re: PlaySound(MAKEINTRESOURCE, IDR_WAVE_RANDOM... problem

lctrncs4-Sep-09 9:06

lctrncs

4-Sep-09 9:06

Thanks to everyone at CodeProject!

It appears that the original post may not be clear.

Therefore, consider the following code snippet which includes much more information about the problem and the (failed) attemtps to resolve it.

Again, for reasons this beginner has yet to understand, PlaySound works fine with a filename constructed from a CString and a random number (/path/filename1.wav), but fails when concatenated CStrings are used to create a resouce identifier (IDR_WAVE_1).

Please consider the code and coments below.

//Create random resource ID (similar approach used to create random wave file names)

	int m_nRandomSound;
	m_nRandomSound = getrandom( 500, 509  );		//Place the random number into the variable n_nRandomRecord

	CString m_sStrRandomSound;						
	m_sStrRandomSound = "";

	CString m_sStrRandomResourcePrefix;			//Create the resource prefix
	m_sStrRandomResourcePrefix = "IDR_WAVE_";

	m_sStrRandomSound.Format("%d", m_nRandomSound);	//Convert the random integer to a CString


//Concatentate the strings into the resource identifier
	CString m_sStrRandomResourcePrefixWav;
	m_sStrRandomResourcePrefixWav = m_sStrRandomResourcePrefix + m_sStrRandomSound;

	
//Set the resource identifier directly
	CString m_sStrRandomResourcePrefixWav2;
	m_sStrRandomResourcePrefixWav2="IDR_WAVE_503";


//  
//
//Demonstrate function similar method that plays sounds using concatenated CString of path/filename
PlaySound(m_sStrRandomSoundPathWav, GetModuleHandle(NULL),  SND_FILENAME|SND_SYNC );  
          //PLAYS from concatenated CString 
          //(e.g. \path\filename?.wav - where ? is an integer converted to a CString)


PlaySound(MAKEINTRESOURCE(IDR_WAVE_503), GetModuleHandle(NULL),  SND_SYNC|SND_RESOURCE );
          //PLAYS IDR_WAVE_503
          //which is directly entered an not subtituted in any way
//
//
//ATTEMPTS TO EMPLOY CONCATENATED STRING TO PLAY RANDOM WAVE FILE

//PlaySound(MAKEINTRESOURCE(m_sStrRandomResourcePrefixWav), GetModuleHandle(NULL),  SND_SYNC|SND_RESOURCE );
          //error C2440: 'type cast' : cannot convert from 'class CString' to 'unsigned short'
          //included for completeness 


//PlaySound(IDR_WAVE_503, GetModuleHandle(NULL),  SND_SYNC|SND_RESOURCE );	
          //error C2664: 'PlaySoundA' : cannot convert parameter 1 from 'const int' to 'const char *'
          //included for completeness 


PlaySound(m_sStrRandomResourcePrefixWav2, GetModuleHandle(NULL),  SND_SYNC|SND_RESOURCE );
          //Compiles but wav not played - 
          //Visual Studio reports (directly intialized as IDR_WAVE 503) m_sStrRandomResourcePrefixWav as "IDR_WAVE 503"


PlaySound("m_sStrRandomResourcePrefixWav", GetModuleHandle(NULL),  SND_SYNC|SND_RESOURCE );
          //Compiles but wav not played - 
          //Visual Studio reports (CONCATENATED CString IDR_WAVE 503) m_sStrRandomResourcePrefixWav as "IDR_WAVE 503"


//
//
//Attempt to cast the CString to an unsigned short

LPCTSTR pRandomSound = m_sStrRandomResourcePrefixWav.GetBuffer(0);	
LPCTSTR pRandomSound2 = m_sStrRandomResourcePrefixWav2.GetBuffer(0);
//

PlaySound(MAKEINTRESOURCE(pRandomSound2), GetModuleHandle(NULL),  SND_SYNC|SND_RESOURCE );
          //Compiles but wav not played - 
          //Visual Studio reports (directly intialized as IDR_WAVE 503) m_sStrRandomResourcePrefixWav as 0x02bd08bc "IDR_WAVE 503"
//

PlaySound(MAKEINTRESOURCE(pRandomSound), AfxGetResourceHandle(),  SND_SYNC|SND_RESOURCE );
          //Compiles but wav not played - 
          //Visual Studio reports (concatenated as IDR_WAVE 503) m_sStrRandomResourcePrefixWav as 0x02bd092c "IDR_WAVE 503"
//

PlayWav(pRandomSound);      //A different approach employing loading/locking resource
          //behaves similarly
          //Compiles but wav not played - 
          //Visual Studio reports (concatenated as IDR_WAVE 503) m_sStrRandomResourcePrefixWav as 0x02bd092c "IDR_WAVE 503" etc.
//

m_sStrRandomResourcePrefixWav.ReleaseBuffer();
m_sStrRandomResourcePrefixWav2.ReleaseBuffer();

Thank you again.

Your comments and suggestions are greatly appreciated.

How to create detailed log.txt file in C programming.

mohant$.net3-Sep-09 3:00

mohant$.net

3-Sep-09 3:00

Hi All

How to create detailed log.txt file in C programming.

As of now am using
fp=fopen("log.txt","a");
fprintf(fp, "Input string = %s\n", Work);

But i want to write log file with much details which is help me to debug.Please gimme me if any prebuild code or related link.

Thanks,
Mohan.T

Mohan t working for N.I.C

Re: How to create detailed log.txt file in C programming.

Hamid_RT3-Sep-09 3:28

Hamid_RT

3-Sep-09 3:28

You can use of WriteFile.

Of one Essence is the human race
thus has Creation put the base
One Limb impacted is sufficient
For all Others to feel the Mace
(Saadi )

Re: How to create detailed log.txt file in C programming.

Maximilien3-Sep-09 3:44

Maximilien

3-Sep-09 3:44

In C (assuming you are really programming in pure C), you will probably not find that much code for that (I tried a few google, and found nothing usefull)

But it should be quite simple to do.

Declare a few global functions that will open the file write to the file, close the file...

What you put in the file is really up to you; no tool will completly do what you want.

If you are looking for C++ code there are some example here, on CP (for example :
Advanced Logging for all kind of applications[^] )

This signature was proudly tested on animals.

Re: How to create detailed log.txt file in C programming.

David Crow3-Sep-09 5:10

David Crow

3-Sep-09 5:10

mohant$.net wrote:
fprintf(fp, "Input string = %s\n", Work);

But i want to write log file with much details which is help me to debug.Please gimme me if any prebuild code or related link.

So why can't you add more fprintf() calls, or add more arguments to the one you are already using?

Re: How to create detailed log.txt file in C programming.

C^hris L^osinger3-Sep-09 11:31

C^hris L^osinger

3-Sep-09 11:31

CSAStatusLog - status logger[^]

image processing toolkits | batch image processing

Cursor freeze in rich edit control

theCPkid3-Sep-09 2:47

theCPkid

3-Sep-09 2:47

I have a CRichEditCtrl derived object which resizes itself whenever the size of text inside it exceeds the control size. This control is a child of CWnd derived object and I am resizing using MoveWindow. THe problem is whenever I resize the window, cursor stops blinking. i can still type the text and it is displayed in the control but the cursor remains static and does not blink.
what can be the reason for this? I tried forcing SetCapture in PreTranslateMessage but nothing seems to work. Sigh | :sigh:

Re: Cursor freeze in rich edit control

Code-o-mat3-Sep-09 4:20

Code-o-mat

3-Sep-09 4:20

Maybe try moving the cursor with CRichEditCtrl::SetSel[^] (you could use GetSel to determine where the cursor should be maybe)

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> Life: great graphics, but the gameplay sux. <

Re: Cursor freeze in rich edit control

theCPkid4-Sep-09 21:19

theCPkid

4-Sep-09 21:19

After two disappointing days, the problem was found to be with parent window CWnd object. making rich edit control a child of cdialog works correctly. Sleepy | :zzz:

anyway, thanks for the reply.

How can i chk the file is readonly or not?

Le@rner3-Sep-09 1:40

Le@rner

3-Sep-09 1:40

Hi all,

I m using CFile to open any text file,i want to detect that the selected file is readonly or not.

please tell me how can i chk the selected file is readonly or not.

thanks in advance.

To accomplish great things, we must not only act, but also dream;
not only plan, but also believe.

Re: How can i chk the file is readonly or not?

Michael Schubert3-Sep-09 1:44

Michael Schubert

3-Sep-09 1:44

That information is hidden in the documentation:
http://msdn.microsoft.com/en-us/library/fa0hc0ht%28VS.80%29.aspx[^]

Re: How can i chk the file is readonly or not?

Le@rner3-Sep-09 1:57

Le@rner

3-Sep-09 1:57

CFileStatus status;
if( CFile::GetStatus( OpenFile, status ) )
{
  if(status.m_attribute==0x01)
   AfxMessageBox(_T("readOnly"));
}

but the messagebox not displayed.or when i debug the code in place of status.m_attribute the '!' display.

To accomplish great things, we must not only act, but also dream;
not only plan, but also believe.

Re: How can i chk the file is readonly or not?

Michael Schubert3-Sep-09 2:07

Michael Schubert

3-Sep-09 2:07

You have to put a mask on the attribute byte to check the read only bit:

if (status.m_attribute & 0x01)
  //it's read-only

Re: How can i chk the file is readonly or not?

Richard MacCutchan3-Sep-09 2:08

Richard MacCutchan

3-Sep-09 2:08

"_$h@nky_" wrote:
if(status.m_attribute==0x01)

It should read

if(status.m_attribute & 0x01)

m_attribute is a bit field which can contain more than one bit setting; check the documentation for the significance of the other bits.

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