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Sleep(0) plainly does nothing, and so you're going to start another thread, but at the same time, have your main thread check a bool over and over again, as fast as it can ?
The mechanisms like WaitForSingleEvent exist precisely to stop people doing stuff like a hard loop to check a bool.
Christian Graus - Microsoft MVP - C++
Metal Musings - Rex and my new metal blog
"I am working on a project that will convert a FORTRAN code to corresponding C++ code.I am not aware of FORTRAN syntax" ( spotted in the C++/CLI forum )
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e...But i see WaitForSingleObject sources also use do {}while(...), Sleep and WaitForSingleObject sources as much as same....
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CPU resources... a while the is always looping takes al the computer resources in order to be done as fast as possible, in the other way is like a callback, the OS handles it...
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I've given my five to Mr. Graus... 
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I have two functions:
getBuffer();
setBuffer();
Assuming the client calls setBuffer() and passes a pointer to a memory block where data is stored, would it be bad practice to have my object modify that block directly, possibly resizing the block itself?
Doing this seems bad practice, as it would indirectly make getBuffer() pointless, but resizing the memory block would screw everything up wouldn't it? Or does the fact the buffer is completed by a NULL byte allow for such scenarios?
Hopefully my question has made sense? 
Cheers
I'm finding the only constant in software development is change it self.
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Hockey wrote: would it be bad practice to have my object modify that block directly, possibly resizing the block itself ... but resizing the memory block would screw everything up wouldn't it
Modify how ?
Resizing would be bad as you probably haven't specified what heap the block is from.
Even if you are using alloc/free new/delete everywhere there may be issues (if multiple modules have statically linked to CRT).
...cmk
Save the whales - collect the whole set
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Interesting! Yes it would be bad practice to have the object modify the size of a buffer it knows nothing about, but it would also be bad practice not to have the object do its own buffer allocations and releases.
Example: char buffer[128]; setBuffer(buffer, cbSize);
As you can see, I just misused your function.
Unless you have a very good reason not to, then you should use the C++ vector class for your buffers. If your object needs a buffer it should allocate it internally and have control over its life time.
INTP
"Program testing can be used to show the presence of bugs, but never to show their absence."Edsger Dijkstra
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Has anyone out there ever successfully done automatic proxy detection?
To be specific -- there's 2 types. There's configuration from IE's static settings.
But IE also supports a automatic proxy detection javascript -- FindProxyForUrl?
I am having a heck of a time finding a method that works.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~<br />
Peter Weyzen<br />
Staff Engineer<br />
<A HREF="http://www.soonr.com">SoonR Inc.</A>
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How can I set the uniform axis property of mschart in VC++2005?
in VB we can use .plot.UniformAxis=FALSE
But how can we do that in VC?
thanks!
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is there anybody who knows that?
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chart.GetPlot().SetUniformAxis()?
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What do you mean?
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GetPlot()should be get_Plot()
but no this function, set_UniformAxis().
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Well, I don't know, you could always open directly the ocx control with the ole/view utility that comes with VC++6, if you don't have that VC++ you can download it from Microsoft.
In that utility you can always choose the first option in the first menu and view the typelib (selecting the same ocx) and then you'll be able to see all that that control exports.
Then you shold be able to see how to do that.
An ActiveX control has it's members inside, so all the languages that must use it should be able to do it. A couple of weeks ago, I was not able to reach a couple of functions in an OCX from VC++2005 and in fact it was possible from Delphi.
Hope this helps.
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I have a c++ codes for programming the parallel port to control an interfce circuit of 8 electrical devices.But this code did not work on WIN XP.how can convert these codes to visual c++ in order for me to incorporate inpout32.dll.Thanks
this is the code:
/*program to control devices using PC parallel port
The devices are controlled by pressing the keys 1-8
that corresponds to each of the 8 possible devices
*/
#include<dos.h>
#include<stdio.h>
#include<conio.h>
#define PORT 0x378 /* This is the parallel port address */
main()
{
char val=0,key=0;
char str1[]="ON ";
char str2[]="OFF";
char *str;
clrscr();
printf("Press the approriate number key to turn on/off devices:\n\n");
printf("Here Device1 is connected to D0 of parallel port and so on\n\n");
printf("Press \"x\" to quit\n\n");
gotoxy(1,8);
printf("Device1:OFF Device2:OFF Device3:OFF Device4:OFF\n");
printf("Device5:OFF Device6:OFF Device7:OFF Device8:OFF");
while(key!='x' && key!='X')
{
gotoxy(1,12);
printf("Value in hex sent to the port:");
key=getch();
switch(key){
case '1':
gotoxy(9,8);
val=(val&0x01)?(val&(~0x01)):val|0x01;
str=(val&0x01)?str1:str2;
printf("%s",str);
outportb(PORT,val);
gotoxy(1,13);
printf("%x",val);
break;
case '2':
gotoxy(21,8);
val=(val&0x02)?(val&(~0x02)):val|0x02;
str=(val&0x02)?str1:str2;
printf("%s",str);
outportb(PORT,val);
gotoxy(1,13);
printf("%x",val);
break;
case '3':
gotoxy(33,8);
val=(val&0x04)?(val&(~0x04)):val|0x04;
str=(val&0x04)?str1:str2;
printf("%s",str);
outportb(PORT,val);
gotoxy(1,13);
printf("%x",val);
break;
case '4':
gotoxy(45,8);
val=(val&0x08)?(val&(~0x08)):val|0x08;
str=(val&0x08)?str1:str2;
printf("%s",str);
outportb(PORT,val);
gotoxy(1,13);
printf("%x",val);
break;
case '5':
gotoxy(9,9);
val=(val&0x10)?(val&(~0x10)):val|0x10;
str=(val&0x10)?str1:str2;
printf("%s",str);
outportb(PORT,val);
gotoxy(1,13);
printf("%x",val);
break;
case '6':
gotoxy(21,9);
val=(val&0x20)?(val&(~0x20)):val|0x20;
str=(val&0x20)?str1:str2;
printf("%s",str);
outportb(PORT,val);
gotoxy(1,13);
printf("%x",val);
break;
case '7':
gotoxy(33,9);
val=(val&0x40)?(val&(~0x40)):val|0x40;
str=(val&0x40)?str1:str2;
printf("%s",str);
outportb(PORT,val);
gotoxy(1,13);
printf("%x",val);
break;
case '8':
gotoxy(45,9);
val=(val&0x80)?(val&(~0x80)):val|0x80;
str=(val&0x80)?str1:str2;
printf("%s",str);
outportb(PORT,val);
gotoxy(1,13);
printf("%x",(unsigned char)val);
break;
}
}
}
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You need to create a low level driver, as modern operating systems do not normally allow you to access the hardware directly.
Good news: There is a freeware version that will allow you to do this; just install and call.
Bad news: I do not remember its name, but if I could find it while researching the subject, 5 years ago, so can you.
Good Luck!
INTP
"Program testing can be used to show the presence of bugs, but never to show their absence."Edsger Dijkstra
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hi all
i am undergoing a project which converts wave file to Mp3.
Inorder to design this audio format converter i am considering the mp3 algo which has following steps:-
1.divide the data into frames such that each frame lasts for 1 sec.
so by the field in header named bits per sample,i have divided the frames.for eg if bits per sample is 8 ie there will be 8 bits or 1 char in each frame and so on...........
in addition to this there are following steps:--
1.if two notes are played at a single time and they are exactly same,only one of them shoudl be retained.
2. if two notes are playing at the same time,but one is of higher freq and one is of lower,only higher one shoudl be retained.
i have traversed the wave header and accesed the data,but that data is in ascii form.
so on that data how can apply the above 2 steps. the wave header is also not giving me any help.
any help is welcome
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puneet_cha wrote: i have traversed the wave header and accesed the data,but that data is in ascii form.
Huh? There may be some ASCII there, but there's more.
WAVE PCM soundfile format[^]
Mark
"Posting a VB.NET question in the C++ forum will end in tears." Chris Maunder
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hi,
AM using Playsound to play a wave file with a click of a button,but if i want to control the volume with another button,is it possible? Pls advice for a step by step guide..
Thannks in advance
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hi,
Am using PlaySound and due to some constraints am not able to use MCI.
Thanks
Pls advice
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I successeded hooking the WSARec for read only:
I hooked the following:
INT WINAPI WSARecvHookProc(SOCKET s, LPWSABUF lpBuffers, DWORD dwBufferCount, LPDWORD lpNumberOfBytesRecvd, LPDWORD lpFlags, LPWSAOVERLAPPED lpOverlapped, LPWSAOVERLAPPED_COMPLETION_ROUTINE lpCompletionRoutine)
My question is how to write to the hooked buffer. I want to modify a packet with value 1 to 0
how can I rewrite the buffer with the value I want?
I am coding with c++ (VS2005)
Thanks in advance!
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