stack corrupted - C / C++ / MFC Discussion Boards

Re: Performance - Thread vs. Message Pump

Michael Dunn21-Dec-05 7:39

21-Dec-05 7:39

My guess is you're seeing the overhead of context switching between threads. Keep track of the time since the last progress update and only report the progress every X milliseconds. 250ms is a good starting point, but you can increase that time if you don't mind fewer updates to your progress UI.

--Mike--
Visual C++ MVP Cool | :cool:

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"Just because the box has 2 gigabytes of memory doesn't mean you get to use it all!"
-- Rico Mariani, CLR perf guy

Re: Performance - Thread vs. Message Pump

Office Lineman21-Dec-05 9:03

Office Lineman

21-Dec-05 9:03

Having not written (or really considered) explicitly multithreaded applications in nearly 7 years, I had forgotten about those two words: "context switch".

Lowering the frequency of the progress update is a generally good idea, which I will implement shortly. Unfortunately, even removing the progress update completely, I'm still experiencing about a 2:1 slowdown.

I suspect this threaded program will run better--at least closer to the peek-and-pump program--when I get to my HT-enabled computer, as DavidCrow's observation would imply.

Thanks a lot! Big Grin | :-D

[gb]

--
I've killed again, haven't I?

Re: Performance - Thread vs. Message Pump

David Crow21-Dec-05 8:06

David Crow

21-Dec-05 8:06

Office Lineman wrote:
They both worked, but the threaded version took almost 3 times as long to complete.

Multi-threaded applications on a uni-processor machine generally run slower.

"Take only what you need and leave the land as you found it." - Native American Proverb

Re: Performance - Thread vs. Message Pump

Office Lineman21-Dec-05 9:28

Office Lineman

21-Dec-05 9:28

Wow.

I forgot I had an old dual 500-MHz machine here. I changed the progress update frequency on both applications, then took this test to it. I had to bump the test up to 100,000,000 iterations to tell the difference!

The peek-and-pump program took 47.6 seconds, and the threaded program took 46.8.

You guys are awesome. I officially unfurl my brow at the worker thread. Laugh | :laugh:

Thanks,
[gb]

--
I've killed again, haven't I?

-- modified at 15:29 Wednesday 21st December, 2005

Resize a window in runtime

sam117321-Dec-05 6:10

sam1173

21-Dec-05 6:10

how can i resize the window (frame and client area) of my app, when i create it, when load a document and when i create a new document

thanks!

Re: Resize a window in runtime

Rage21-Dec-05 6:18

Rage

21-Dec-05 6:18

Use MoveWindow or SetWindowPos in the appropriate message handlers (I suppose you have MFC, so this must be in OnCreate, OnOpen and so on. I am not so familiar with SDI/MDI)

~RaGE();

problem retrieiving wmiClass info

WetRivrRat21-Dec-05 3:16

WetRivrRat

21-Dec-05 3:16

hey guys,
just wondering if any of you guys happen to visit the C# forum any, as I posted a question there hoping someone could help, but it seems that no one in the C# world can, or i'm just asking for the wrong info...
either way just wondering if someone could go check it out and see if they know anything...

here's the link:
http://codeproject.com/script/comments/forums.asp?forumid=1649&fr=76&select=1312256#xx1312256xx[^]

I'm basicly trying to find a way to access info on my hardware that i know exist, have found it using other software tools, and would like to reproduce with my own code. I understand that I may run into a problem trying to access this info through managed code, so if any of you know which "yellow brick road" to follow and are willing to help me out I would appreciate it TREMENDOUSLY!!!

Thanks in advance
Merry Christmas,
Happy Hanukkah!

-

string Beautiful;
Beautiful = "ignorant";
label1.Text = "The world is full of " + Beautiful +" people.";

Why is common sense such an un-common comodity?

stack corrupted

iiscodered21-Dec-05 2:29

iiscodered

21-Dec-05 2:29

HI,
i have a problem with this function...

void show(){

int hour,minu,sec;
char time1;

hLUIseDLL = LoadLibrary("LUIse.dll");
if (hLUIseDLL != NULL)
{
LUI_OpenDevice = (T_LUI_OpenDevice)GetProcAddress(hLUIseDLL, "LUI_OpenDevice");
LUI_CloseDevice = (T_LUI_CloseDevice)GetProcAddress(hLUIseDLL, "LUI_CloseDevice");
LUI_DispOnOff = (T_LUI_DispOnOff)GetProcAddress(hLUIseDLL, "LUI_DispOnOff");
LUI_CCFL = (T_LUI_CCFL)GetProcAddress(hLUIseDLL, "LUI_CCFL");
LUI_GetContrast = (T_LUI_GetContrast)GetProcAddress(hLUIseDLL, "LUI_GetContrast");
LUI_SetContrast = (T_LUI_SetContrast)GetProcAddress(hLUIseDLL, "LUI_SetContrast");
LUI_OutPort = (T_LUI_OutPort)GetProcAddress(hLUIseDLL, "LUI_OutPort");
LUI_InPort = (T_LUI_InPort)GetProcAddress(hLUIseDLL, "LUI_InPort");
LUI_LCDmode = (T_LUI_LCDmode)GetProcAddress(hLUIseDLL, "LUI_LCDmode");
LUI_Bitmap = (T_LUI_Bitmap)GetProcAddress(hLUIseDLL, "LUI_Bitmap");
LUI_Text = (T_LUI_Text)GetProcAddress(hLUIseDLL, "LUI_Text");
LUI_BMPfile = (T_LUI_BMPfile)GetProcAddress(hLUIseDLL, "LUI_BMPfile");
LUI_SetPixel = (T_LUI_SetPixel)GetProcAddress(hLUIseDLL, "LUI_SetPixel");
LUI_GetSerial = (T_LUI_GetSerial)GetProcAddress(hLUIseDLL, "LUI_GetSerial");
GetDllVersion = (T_GetDllVersion)GetProcAddress(hLUIseDLL, "GetDllVersion");
LUI_ScreenRefreshControl = (T_LUI_ScreenRefreshControl)GetProcAddress(hLUIseDLL, "LUI_ScreenRefreshControl");
LUI_TouchScreen = (T_LUI_TouchScreen)GetProcAddress(hLUIseDLL, "LUI_TouchScreen");
}else MessageBox(0,"DLL Error","Error", MB_OK);

LUI_OpenDevice(0)
LUI_TouchScreen(0,mouse);

do{
if(mouse[1]<300){

CTime t=CTime::GetCurrentTime();
sprintf(&time1,"%d:%d:%d",t.GetDay(),t.GetMinute(),t.GetSecond());

parser.data=&time1;
parser.draw();
LUI_TouchScreen(0,mouse);

Sleep(200);

}while(mouse[1]<=300);

LUI_CloseDevice(0);
Sleep(200);

FreeLibrary(hLUIseDLL);
}

the debugger says that the stack around the time1 is corrupted(runtime errot #2), but...what to do?
when i set the configurationmode to "release", it runs, but time1 isn't the value.
please help me...

thanks

-- modified at 8:29 Wednesday 21st December, 2005

Re: stack corrupted

JCO66321-Dec-05 2:41

JCO663

21-Dec-05 2:41

try the following declaration: char time1[64];
and replace &time1 by just time1.
you are writing too many chars in your time1 in the sprintf.

Re: stack corrupted

toxcct21-Dec-05 2:55

toxcct

21-Dec-05 2:55

dude !!!

you resposted your question, ,but it seems that you didn't even tried what i already answered you last day[^]... Frown | :(

TOXCCT >>> GEII power
[toxcct][VisualCalc 2.20][VisualCalc 3.0]

Re: stack corrupted

iiscodered21-Dec-05 3:47

iiscodered

21-Dec-05 3:47

sorry toxxcct, your solution worked(thx), but i'm a beginner in visual c++ (i programmed borland before) and i hate this type conversion.

Re: stack corrupted [edited]

toxcct21-Dec-05 3:49

toxcct

21-Dec-05 3:49

iiscodered wrote:
i hate this type conversion.

if you don't like it, you won't like programming C++ sir !!!

[edit]
i don't know who is that anonymous who voted me 1 for this answer, but here is the point. In C++, we have to manage ourselves the memory allocation/dealocation on the heap, so, when one tells that he doesn't like this way of programming, it makes me laugh because it's a bigger part of the C++ usage...
now if that poor guy cannot show off himself, shame on him.
[/edit]

TOXCCT >>> GEII power
[toxcct][VisualCalc 2.20][VisualCalc 3.0]

-- modified at 3:36 Thursday 22nd December, 2005

GetPixel: How to include cursor icon?

Matrim Cauthon21-Dec-05 1:30

Matrim Cauthon

21-Dec-05 1:30

Hello,

I need to determine the pixel color of a certain area of the screen including the cursor icon.
The GetPixel function receives the pixel color _under_ then cursor Frown | :-(

Any ideas?

Thank you in advance,
Mat.

-- modified at 7:32 Wednesday 21st December, 2005

Re: GetPixel: How to include cursor icon?

Rage21-Dec-05 3:51

Rage

21-Dec-05 3:51

Maybe you can find an hint in this article :

Link[^]

I am not positive, yet.

~RaGE();

Re: GetPixel: How to include cursor icon?

Matrim Cauthon21-Dec-05 6:53

Matrim Cauthon

21-Dec-05 6:53

Thank you for your reply but this version does the same
I'm using quite unsuccessfully right now. It captures any
pixel but the cursor icon Frown | :-(

Mat.

Re: GetPixel: How to include cursor icon?

basementman21-Dec-05 8:57

basementman

21-Dec-05 8:57

You need to get the cursor bitmap, offset into the bitmap from the cursor x/y origin to the location you wish to extract and read the bitmap colors.

Try

ICONINFO sIconInfo;
GetIconInfo(GetCursor(),&sIconInfo));

to extract the image and reference the image via sIconInfo.bmColor member.

onwards and upwards...

u use the Getpixel for picture dc

Member 22716555-Jan-06 22:27

Member 2271655

5-Jan-06 22:27

u use the Getpixel for picture dc

happy new year

Re: u use the Getpixel for picture dc

basementman6-Jan-06 4:08

basementman

6-Jan-06 4:08

or read the RGBQUADs directly...

onwards and upwards...

Initializing Structure in a class

vikas amin21-Dec-05 0:50

vikas amin

21-Dec-05 0:50

I tried to initalise a structure in the class
by

struct tagBITMAPFILEHEADER
{
WORD bfType=0; // must be 'BM'
DWORD bfSize=0; // size of the whole .bmp file
WORD bfReserved1=0; // must be 0
WORD bfReserved2=0; // must be 0
DWORD bfOffBits=0;
}m_BITMAPFILEHEADER ;

there is an error displayed as

error C2252: 'bfType' : pure specifier can only be specified for functions

How to initialise in a class any help

Vikas Amin
Embin Technology
Bombay
vikas.amin@embin.com

Re: Initializing Structure in a class

Rage21-Dec-05 1:11

Rage

21-Dec-05 1:11

vikas amin wrote:
How to initialise in a class

Is this working?

struct tagBITMAPFILEHEADER 
{
WORD bfType; // must be 'BM' 
DWORD bfSize; // size of the whole .bmp file
WORD bfReserved1; // must be 0
WORD bfReserved2; // must be 0
DWORD bfOffBits;
}m_BITMAPFILEHEADER = {0,0,0,0,0};

~RaGE();

Re: Initializing Structure in a class

Owner drawn21-Dec-05 1:13

Owner drawn

21-Dec-05 1:13

vikas amin wrote:
WORD bfType=0; // must be 'BM'
DWORD bfSize=0; // size of the whole .bmp file
WORD bfReserved1=0; // must be 0
WORD bfReserved2=0; // must be 0
DWORD bfOffBits=0;

You cannot init members like that inside a structure.

Create an instance and then initialize the members

Happy christmas friends. May the Love of My Lord and Saviour Jesus bring forth Joy and Happiness into your life too.
<marquee direction="up" height="50" scrolldelay="1" step="1" scrollamount="1" hspace="2" vspace="2">
--Owner Drawn
--Nothing special
--Defeat is temporary but surrender is permanent
--Never say quits
--Jesus is Lord

Re: Initializing Structure in a class

toxcct21-Dec-05 2:03

toxcct

21-Dec-05 2:03

to be more complete, writing such a thing tell the compiler that the members are pure virtual (which is here definitely wrong).

TOXCCT >>> GEII power
[toxcct][VisualCalc 2.20][VisualCalc 3.0]

Re: Initializing Structure in a class

Owner drawn21-Dec-05 19:44

Owner drawn

21-Dec-05 19:44

Game over

Re: Initializing Structure in a class

Eytukan21-Dec-05 2:01

Eytukan

21-Dec-05 2:01

in the constructor , init the strcut variable = {val,val2,...).(positional refernce)

"But your mind is very complex, very tricky. It makes simple things complicated. -- that's its work. And for centuries it has been trained for only one thing: to make things so complicated that your life becomes impossible."- Osho

<marquee scrollamount="1" scrolldelay="1" direction="up" height="10" step="1">
--[V]--

Re: Initializing Structure in a class

toxcct21-Dec-05 2:13

toxcct

21-Dec-05 2:13

Mr vikas,

it's the second time i see this question from you. if you continue asking it exactly the same way, you will get exactly same answers...

to go further in help, i'd like to see how you exactly try to initialize your struct (give a piece a code were you do it, and DON'T FORGET : round your code samples with <pre></pre> tag to help us see you code better !!)

moreover, as it has already been suggested, there are 2 ways to do this :
1st :

m_BITMAPFILEHEADER = { 0, 0, 0, 0, 0 };

2nd :

m_BITMAPFILEHEADER.bfType      = 0;
m_BITMAPFILEHEADER.bfSize      = 0;
m_BITMAPFILEHEADER.bfReserved1 = 0;
m_BITMAPFILEHEADER.bfReserved2 = 0;
m_BITMAPFILEHEADER.bfOffBits   = 0;

if you try to initialize this in your class constructor, did you try also to use the first method in the initilizer list of the constructor ?

<font color=blue>class</font> MyClass {
  <font color=blue>private</font>:
    <font color=blue>struct</font> tagBITMAPFILEHEADER {
        <font color=green>//...</font>
        tagBITMAPFILEHEADER(<font color=blue>const</font> tagBITMAPFILEHEADER&);  <font color=green>//Default constructor</font>
    } m_tagBITMAPFILEHEADER;
 
  <font color=blue>public</font>:
    MyClass()
        : m_tagBITMAPFILEHEADER({ 0, 0, 0, 0, 0 }) {
        <font color=green>//...</font>
    }
};

TOXCCT >>> GEII power
[toxcct][VisualCalc 2.20][VisualCalc 3.0]

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