Sockets without MFC/HWNDs or Spin-Locks? - C / C++ / MFC Discussion Boards

Alvaro Mendez24-Oct-02 10:09

24-Oct-02 10:09

I'd say because it's not worth it. Most warnings should be addressed and fixed, but a few, like this one are just not worth the trouble. I can list you a couple of other compiler warnings which I've disabled:

4786: identifier was truncated to '255' characters in the debug information
4355: 'this': used in base member initializer list

Do you think it's worth fixing these? If so, how would you do it?

Regards,
Alvaro

There is much pleasure to be gained from useless knowledge. - Bertrand Russell

Re: /OPT:REF

Joe Woodbury24-Oct-02 11:28

Joe Woodbury

24-Oct-02 11:28

Michael Dunn wrote:
Why not fix the problem that's causing the warning?

Because often you can't for this specific warning which is generated because the linker COMDAT optimization made the library no longer necessary, though it was before the optimization.

[Link message] 4089 is an purely informational message and should be labeled as such--it is not a warning in any commonly accepted way. In other words, the presence or absence of this warning has no bearing on whether an executable will or will not work.

how can I make a multirow CPropertySheet?

DanYELL24-Oct-02 3:09

DanYELL

24-Oct-02 3:09

I have alot of pages. I can only seem to get 16 pages on one row. Is there away to make ten pages on one row and ten more pages on another row?

Please, any response any one can give me will be greatly appreciated.

Sincerely,
Danielle (an overworked graduate student)

Re: how can I make a multirow CPropertySheet?

Mike Nordell24-Oct-02 3:47

Mike Nordell

24-Oct-02 3:47

You mean something like this?

Re: how can I make a multirow CPropertySheet?

DanYELL24-Oct-02 4:54

DanYELL

24-Oct-02 4:54

Yes, yes, yes. How? How? How?

Re: how can I make a multirow CPropertySheet?

Ravi Bhavnani24-Oct-02 5:10

Ravi Bhavnani

24-Oct-02 5:10

I fake it by padding the tab names with spaces. Not foolproof, but it works almost all the time.

/ravi

Let's put "civil" back in "civilization"
http://www.ravib.com
ravib@ravib.com

I want that TabCtrl!

solosnake24-Oct-02 2:55

solosnake

24-Oct-02 2:55

Hello

I want to add to my application the type of tabbed control that can be seen in MSVC as the 'Workspace' view. Its the tabs with the classview/resource/file tree's that's normally on the rhs of MSVC. How do I do this?

I'm using the doc-view architecture, and I want this CTabCtrl to be in one of two windows in a splitter wnd. It will be used to select between differing views of the data set that is displayed graphically in the rhs split window. There will be a fixed number of viewingmodes, each corresponding to a tab in the lhs tab ctrl.

Could anyone explain to me the sequence of classes I need to create to achieve this type of control? Can each of the tabs in the control represent a 'CView' derived class? Where should I attach them to the tab-ctrl?

All help or comments appreciated. Please don't redirect me to the (great) tab control samples that codeproject has : none of them are what I need, I've looked at them all.

Cheers,

- solosnake

Sockets without MFC/HWNDs or Spin-Locks?

Phil Speller24-Oct-02 2:07

Phil Speller

24-Oct-02 2:07

MFC's ASyncSocket class provides a wrapper around a Win32 socket and adds functionality to detect events (such as connection, packet received etc). Now I'm aware that a similar method can be performed using plain winsock programming and the use of WSAAsyncSelect. However, it requires the use of a window to receive events (CAsyncSocket does it like this as well doesn't it?). I've seen code that sets up a thread and just waits on recv() using a spin-lock - this seems to go against the grain with me though. I have noticed the select() fn, but I'm not sure if it would truly be thread friendly or would just hide a spin-lock. So, to my question: Is it possible to detect an event from a Socket without resorting to window messages or requiring a spin-lock?

Phil

Re: Sockets without MFC/HWNDs or Spin-Locks?

Stephane Rodriguez.24-Oct-02 3:46

Stephane Rodriguez.

24-Oct-02 3:46

A website[^] you'll love.

How low can you go ?
(MS rant)

Re: Sockets without MFC/HWNDs or Spin-Locks?

JT Anderson24-Oct-02 5:54

JT Anderson

24-Oct-02 5:54

You might find WSAEventSelect interesting.

--------
There are 10 types of people in this world. Those who know binary and those who don't.

OwnerDraw ListCtrl problem - help!

Yaron Nir24-Oct-02 1:57

Yaron Nir

24-Oct-02 1:57

Hi all,

I have an owner draw list ctrl.

i want to force a vertical scroll to be shown when the dialog
that the list sits on appears.
this is the code i've tried :

ListView_SetExtendedListViewStyle(m_lc.m_hWnd,
LVS_EX_FLATSB|LVS_EX_FULLROWSELECT );

now i've inserted some columns and then:

m_lc.ModifyStyle(0,WS_VSCROLL);
m_lc.SetScrollRange(SB_VERT,0,100);
m_lc.SetScrollPos(SB_VERT,0);
m_lc.ShowScrollBar(SB_VERT);

this doesn't show the vertical scroll bar.
the bar only show when the limit of inserted items succeeds.

can any1 show me what to do in order to force the scroll bar?

thanks in advanced

Yaron

Ask not what the application can do for you, ask what you can do for your application

Reading a Wav Header

carrie24-Oct-02 1:37

carrie

24-Oct-02 1:37

Hello, I'm on the beg again Smile | :)

I'm trying to read in the header of a wav file. My code so far is..

	<br />
struct<br />
{<br />
	WORD wFormatTag; // Format category<br />
	WORD wChannels; // Number of channels<br />
	DWORD dwSamplesPerSec; // Sampling rate<br />
	DWORD dwAvgBytesPerSec; // For buffer estimation<br />
	WORD wBlockAlign; // Data block size<br />
} FormatChunk;<br />
<br />
	char ch[1];<br />
	CFile waveFile;<br />
	if(waveFile.Open(wavName,CFile::modeRead|CFile::typeBinary)==FALSE)<br />
	{<br />
		TRACE("Error opening file");<br />
		return NULL;<br />
	}<br />
<br />
	//read till we get to the start of above chunk header<br />
	while(1)<br />
	{<br />
		waveFile.Read(ch,1);<br />
		TRACE("%c\n",ch[0]);<br />
		if(ch[0] == 'E')<br />
			break;<br />
	}<br />
<br />
	waveFile.Read(&FormatChunk,sizeof(FormatChunk));<br />
<br />
	DWORD temp = FormatChunk.dwAvgBytesPerSec;<br />
	//FormatChunk.dwAvgBytesPerSec holds the sampling rate <br />
	TRACE("Sampling rate is : %ld\n",temp);<br />
	TRACE("wChannels is : %0.2d\n",FormatChunk.wChannels);<br />
//	TRACE("format tag is : %s\n",FormatChunk.wFormatTag);<br />
<br />
	waveFile.Close();<br />
	return temp;

Ignore the ugliness of it please Smile | :)

My problem is reading in the wChannels value from byte offset 16, its a 2byte value. It should either be 0x10 or 0x20 in the file but I'm having problems reading it right. I've been playing with different variables to get it read right but all I get is either 16 for all of them or something like 8016 Frown | :(

Or have I totally missed the point and theres an API function out there that'll do it for me? Smile | :)

Thanks

Re: Reading a Wav Header

Phil Speller24-Oct-02 2:35

Phil Speller

24-Oct-02 2:35

Accoring to this[^] your FormatChunk structure is incorrect. It should be:

struct
{
DWORD wFormatTag; // Format category
DWORD dwFormatLen; // Length of format chunk - always 0x10
WORD wReserved; // Always 0x01
WORD wChannels; // Number of channels
DWORD dwSamplesPerSec; // Sampling rate
DWORD dwAvgBytesPerSec; // For buffer estimation
WORD wBytesPerSample;
WORD wBitsPerSample;
} FormatChunk;

Hope this helps,

Phil

Re: Reading a Wav Header

carrie24-Oct-02 2:50

carrie

24-Oct-02 2:50

Phil, thou art a god Smile | :)

Knew it had to be something stupid that I was doing, thanks for that link too Smile | :)

/me gets out my winsocks books to see about your question Smile | :)

error message is Popped up when..

BK Pradeep24-Oct-02 0:51

BK Pradeep

24-Oct-02 0:51

Hi ,
I am trying to access a property of an activex control and in
code statement
InvokeHelper() it pops up a message box telling its a runtime property.

how to avoid this??

waiting for ur replies eagerly.

pradeep

Whose problem?ListView or database?

ratios24-Oct-02 0:07

ratios

24-Oct-02 0:07

Suppose I have a database,which involves a table containing more than 10 thousand records.The structure of the table is:
table name: custom
collumn: custom_id,custom_name,custom_address

Now I should get all the records from the table by ODBC and show them in a Listview.
But a strange problem occurs:the listview only shows nearly 500 records,the others are blank except the custom_id.
It baffled me completely.Why the listview cannot show all the records?Does it have the limitation?If I limit the condition,just like"select * from custom where custom_id between 1 and 1000".I'm surprise to see the listview show the 1000 records.Which has problem,the listview or the databse?
Who can tell why?
Thank you for your kindness.

Re: Whose problem?ListView or database?

Michael P Butler24-Oct-02 1:02

Michael P Butler

24-Oct-02 1:02

ListView should cope with more than 1000 records, although from a design point of view this is a bad idea.

Can you post some code as I suspect you have a bug somewhere.

Michael

"I've died for a living in the movies and tv.
But the hardest thing I'll ever do is watch my leading ladies,
Kiss some other guy while I'm bandaging my knee."
-- The Unknown Stuntman

Re: Whose problem?ListView or database?

Steve S24-Oct-02 2:43

Steve S

24-Oct-02 2:43

Michael P Butler wrote:
although from a design point of view this is a bad idea.

Which is, of course, why there's an Owner Data style. It's non-trivial to hook up to a dynamic recordset, since there are issues with deleted records, but for simple selection it's fairly simple.

Steve S
One day, I'll have a good signature...

Subclassing problem

Mazdak23-Oct-02 23:30

Mazdak

23-Oct-02 23:30

I have a class that subclass from CEdit.Now I want to subclass from this class.After I make generic class and subclass it from that class,after compiling I got many errors in my base class.Also I got an error that:

error C2504: 'CEdit' : base class undefined

Mazy

"If I go crazy then will you still
Call me Superman
If I’m alive and well, will you be
There holding my hand
I’ll keep you by my side with
My superhuman might
Kryptonite"Kryptonite-3 Doors Down

Re: Subclassing problem

Simon.W24-Oct-02 1:15

Simon.W

24-Oct-02 1:15

Make sure whether you include MFC header file

I am seeking...
For what?
Why did you ask me for what? I don't know!

Re: Subclassing problem

Mazdak24-Oct-02 1:43

Mazdak

24-Oct-02 1:43

XSimon wrote:
MFC header

Could you name them please?

Mazy

"If I go crazy then will you still
Call me Superman
If I’m alive and well, will you be
There holding my hand
I’ll keep you by my side with
My superhuman might
Kryptonite"Kryptonite-3 Doors Down

How to sort CArray?

ooosawaddee323-Oct-02 22:58

ooosawaddee3

23-Oct-02 22:58

I declare this below data.

[code]
CArray<unsigned char,="" unsigned="" char=""> m_data1, m_data2, m_data3, m_data4;
[/code]

I want to to sort m_data1, m_data2, m_data3, m_data4.
If you know how to do that, please tell me.

Thank you very much.

Re: How to sort CArray?

Christian Graus24-Oct-02 0:24

Christian Graus

24-Oct-02 0:24

I honestly don't know, but this is one major reason why you'd be better off to ditch CArray for std::vector. I have a number of articles here on CP with regard to the STL to get you started.

Christian

No offense, but I don't really want to encourage the creation of another VB developer. - Larry Antram 22 Oct 2002

Hey, at least Logo had, at it's inception, a mechanical turtle. VB has always lacked even that... - Shog9 04-09-2002

During last 10 years, with invention of VB and similar programming environments, every ill-educated moron became able to develop software. - Alex E. - 12-Sept-2002

Re: How to sort CArray?

Atlantys24-Oct-02 3:34

Atlantys

24-Oct-02 3:34

CArray doesn't have a built-in Sort function. So you'd either have to write your own (using Quicksort and friends).

I'd suggest just scrapping the whole idea of using CArray (and MFC collections) and move onto std::vector and std::sort (i used to be an MFC junkie, but I've been converted to STL Big Grin | :-D

Re: How to sort CArray?

Mike Eriksson25-Oct-02 0:06

Mike Eriksson

25-Oct-02 0:06

Hello!

Since you already have gotten a couple of suggestion to use STL, I thought I give you what you asked for Poke tongue | ;-P

Here on CodeProject there is a article about this!
Mr. Martin Ziacek has described how to use quicksort together with CArray.

http://www.codeproject.com/cpp/qarray.asp

Mike Eriksson
Sonork 100.21825

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