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Re: C - memory functions vs. Win32 memory functions Joaquín M López Muñoz21-May-02 0:50 Joaquín M López Muñoz 21-May-02 0:50  I assume the Win32 memory functions are faster, but how much? Actually, FillMemory and colleagues are macros for memset These are not real Win32 functions, but rather they're resolved usually as inline code. Apart from this, Mish wisely pointed out the convenience of not using platform-specific APIs if they're are so easily avoidable as these. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo Re: C - memory functions vs. Win32 memory functions Alexandru Savescu21-May-02 0:58 Alexandru Savescu 21-May-02 0:58  Ok, thanks, I thought there were somehow "more built in" in the OSs architecture. Best regards, Alexandru Savescu Re: C - memory functions vs. Win32 memory functions Nish Nishant21-May-02 1:16 Nish Nishant 21-May-02 1:16  Joaquín M López Muñoz wrote: Mish wisely pointed out Mish???? Nish Regards, Nish Native CPian. Born and brought up on CP. With the CP blood in him. Re: C - memory functions vs. Win32 memory functions Joaquín M López Muñoz21-May-02 2:23 Joaquín M López Muñoz 21-May-02 2:23  Oh, forgive the typo I was talking about you, of course. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo Re: C - memory functions vs. Win32 memory functions Alexandru Savescu21-May-02 2:35 Alexandru Savescu 21-May-02 2:35  At least he said you did smth wisely Best regards, Alexandru Savescu Re: C - memory functions vs. Win32 memory functions moliate21-May-02 1:03 moliate 21-May-02 1:03  I assume that functions like ZeroMemory will eventually call memset. A debug stepping confirmed this (for a dialog based app, debug build) About speed - testing with RDTSC gave the following result when filling a 10'000 byte array: [modified](This seems odd when I read the response above. Perhaps this is just a debug mode thing)[/modified] memset: 2753 ticks ZeroMemory: 4255 ticks I might add that this was also a debug build. [modified]Yes, under Release no difference in the execution time could be measured.[/modified] /moliate Re: C - memory functions vs. Win32 memory functions Tim Smith21-May-02 1:48 Tim Smith 21-May-02 1:48  Performance testing under debug is pointless. Tim Smith I know what you're thinking punk, you're thinking did he spell check this document? Well, to tell you the truth I kinda forgot myself in all this excitement. But being this here's CodeProject, the most powerful forums in the world and would blow your head clean off, you've got to ask yourself one question, Do I feel lucky? Well do ya punk? Re: C - memory functions vs. Win32 memory functions moliate21-May-02 2:50 moliate 21-May-02 2:50  Tim Smith wrote: Performance testing under debug is pointless. I didn't think it would make a difference in this case since the same code is called. Suppose I have to take a closer look at the Debug/Release differences (again...) /moliate Two o'clock and walking through familiar London - Or what was familiar London before the cursor deleted certain certainties - I watch a suit and tie man giving suck to the Psion Organizer lodged in his breast pocket its serial interface like a cool mouth hunting his chest for sustenance, familiar feeling, and I'm watching my breath steam in the air. Neil Gaiman - Cold Colours Re: C - memory functions vs. Win32 memory functions Tim Smith21-May-02 3:45 Tim Smith 21-May-02 3:45  You could be right. But it has always been my opinion to just go ahead and test in release mode. Then you don't have to guess if it might make a difference. Tim Smith I know what you're thinking punk, you're thinking did he spell check this document? Well, to tell you the truth I kinda forgot myself in all this excitement. But being this here's CodeProject, the most powerful forums in the world and would blow your head clean off, you've got to ask yourself one question, Do I feel lucky? Well do ya punk? Re: C - memory functions vs. Win32 memory functions James R. Twine21-May-02 5:30 James R. Twine 21-May-02 5:30     I was under the impression that using RDTSC (alone) in a true multi-tasking environment would not yield accurate results due to the fact that the OS is busy doing other things, and your code, no matter how small, might get suspended/swapped.    Peace! -=- James. "Fat people are hard to kidnap." (Try Check Favorites Sometime!) Re: C - memory functions vs. Win32 memory functions Tim Smith21-May-02 6:12 Tim Smith 21-May-02 6:12  This is very true. Which is why you run your tests for a long time and multiple times. There are also things you do to try and make sure all you program code is paged in. But generally, you never test for raw speed (i.e. X runs in 506ms). You should always test for relative speed (i.e. X runs 23% faster than Y). This helps to make sure that both tests for X and Y are performed in the same environment. Also, test for repeatability. Tim Smith I know what you're thinking punk, you're thinking did he spell check this document? Well, to tell you the truth I kinda forgot myself in all this excitement. But being this here's CodeProject, the most powerful forums in the world and would blow your head clean off, you've got to ask yourself one question, Do I feel lucky? Well do ya punk? Re: C - memory functions vs. Win32 memory functions Tim Smith21-May-02 6:14 Tim Smith 21-May-02 6:14  What I am trying to say is that even though what you said is very true. There are things that you can do to still make performance measurement reasonably reliable. Tim Smith I know what you're thinking punk, you're thinking did he spell check this document? Well, to tell you the truth I kinda forgot myself in all this excitement. But being this here's CodeProject, the most powerful forums in the world and would blow your head clean off, you've got to ask yourself one question, Do I feel lucky? Well do ya punk? Re: C - memory functions vs. Win32 memory functions Joao Vaz21-May-02 2:53 Joao Vaz 21-May-02 2:53  moliate wrote: ZeroMemory If recall correctly Zero Memory is a memset that fills 0's in the destination adress. Cheers, Joao Vaz A person who is nice to you, but rude to the waiter, is not a nice person - Natalie Portman (Padme/Amidala of Star Wars) Re: C - memory functions vs. Win32 memory functions moliate21-May-02 3:14 moliate 21-May-02 3:14  Yes, but Joaquín told us it was a macro rather than a function. That's why I found it so odd to get different results on the memset/ZeroMemory. Apparantly it is never safe to do even the simplest performance testing in a Debug build. Lesson learned. /moliate Two o'clock and walking through familiar London - Or what was familiar London before the cursor deleted certain certainties - I watch a suit and tie man giving suck to the Psion Organizer lodged in his breast pocket its serial interface like a cool mouth hunting his chest for sustenance, familiar feeling, and I'm watching my breath steam in the air. Neil Gaiman - Cold Colours Re: C - memory functions vs. Win32 memory functions Joao Vaz21-May-02 3:50 Joao Vaz 21-May-02 3:50  moliate wrote: Yes, but Joaquín told us it was a macro rather than a function. Yeap, Joaquin is right moliate wrote: do even the simplest performance testing in a Debug build. Lesson learned The allocation of memory is monitored in debug builds by the CRT , so it fakes the results ... Actually ZeroMemory is a macro using the RtlZeroMemory that is also a Macro that uses ... Cheers, Joao Vaz A person who is nice to you, but rude to the waiter, is not a nice person - Natalie Portman (Padme/Amidala of Star Wars) Re: C - memory functions vs. Win32 memory functions Tim Smith21-May-02 3:59 Tim Smith 21-May-02 3:59  Actually ZeroMemory is a macro using the RtlZeroMemory that is also a Macro that uses ... WTF????? ZeroMemory sub contracts the work out to RtlZeroMemory? I didn't authorize subcontractors!!!! Tim Smith I know what you're thinking punk, you're thinking did he spell check this document? Well, to tell you the truth I kinda forgot myself in all this excitement. But being this here's CodeProject, the most powerful forums in the world and would blow your head clean off, you've got to ask yourself one question, Do I feel lucky? Well do ya punk? Re: C - memory functions vs. Win32 memory functions Joao Vaz21-May-02 4:09 Joao Vaz 21-May-02 4:09  Tim Smith wrote: ZeroMemory sub contracts the work out to RtlZeroMemory? And guess what ? The RtlZeroMemory does a simple memset !!!! #define RtlZeroMemory(Destination,Length) memset((Destination),0,(Length)) Tim Smith wrote: I didn't authorize subcontractors!!!! Cheers, Joao Vaz A person who is nice to you, but rude to the waiter, is not a nice person - Natalie Portman (Padme/Amidala of Star Wars) Re: and macro definition Joao Vaz21-May-02 4:11 Joao Vaz 21-May-02 4:11  Duhhhhhhhhhhhhhhh ! #define RtlZeroMemory(Destination,Length) memset((Destination),0,(Length)) Cheers, Joao Vaz A person who is nice to you, but rude to the waiter, is not a nice person - Natalie Portman (Padme/Amidala of Star Wars) Re: C - memory functions vs. Win32 memory functions James R. Twine21-May-02 5:25 James R. Twine 21-May-02 5:25     Also consider the fact that you can use intrinsic versions of the memset(...), memcpy(...), etc. functions.    Peace! -=- James. "Fat people are hard to kidnap." (Try Check Favorites Sometime!) How to handle LButtonDown message of a list box in combobox? denkor20-May-02 23:42 denkor 20-May-02 23:42  Hello guys: I want to creat a combobox in which user can change item state(for example: on/off) when the list box is displayed.User can toggle item state by clicking left part and selet a item by clicking the right part. The question is how to handle mousedown message of dropped down list box? Thank you very much to give me some advice! example: <a href="http://www.codeguru.com/forum/attachment.php?s=&postid=524383">demo.jpg</a> No one knows? No one help me? denkor21-May-02 2:29 denkor 21-May-02 2:29  why no response? Socket I/O 20-May-02 23:36 20-May-02 23:36  Hi, does anyone have some idea, how to make some TCP network transfer in separate thread (open connection, send/receive some data, close connection, end thread) using WinSock 1.1, so that i can immediately stop thread from parent thread anytime ? Re: Socket I/O Joaquín M López Muñoz21-May-02 0:40 Joaquín M López Muñoz 21-May-02 0:40  One approach is this: launch a thread provided with a message pump, and use message-based asynchronous sockets (see WSAAsyncSelect for further info). This thread can be stopped at any time with PostQuitMessage. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo MFC Fonts 20-May-02 23:18 20-May-02 23:18  Actually the problem is very small . I am using DrawText function . and i want to display the font ac per the system setting so please if anybody can help me wating for the reply. Re: MFC Fonts jack Mesic21-May-02 5:28 jack Mesic 21-May-02 5:28  Hi, this link may help you: http://www.ucancode.net/ It shows the advance gdi and font features you like. The client may interest you. Regards jack

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