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Thank you very much for the reply. But correct me if I'm wrong.
When sending TCP with Winsock, doesn't Winsock package the packets with extra headers once it reaches the Link Layer of the OSI model. Actually, at every stage a corresponding header is append to the packet, i.e. IP layer, IP header is added to the packet? Once the packet reaches the Link or Hardware Layer, the system performs an ARP cache lookup to see if the destination IP resolves to a mac address. If it does, the system sends the packet off. If not, it performs a mac address broadcast (ARP lookup) and wait for a reply to who this packet belongs to.
If this is true, then can't we create a raw package with all the correct headers, except the IP address section which is set to NULL and send it off? On each client, have it listen for incoming messages and have it do some packet verification at the Network Card Driver level (NDIS).
I have looked into NDIS, and believe it is the solution to this problem. The only thing I'm not sure of is, upon a TCP/IP send in general, is this packet broadcast or sent directly to the destination? If it is sent directly to the destination, how does it know where to go, without having to go through every other non-destination hosts?
The Internet or Intranet consist of more than one PC. As such, there is no hard wire link from source to destination. Which lead me to believe that at the Link/Hardware level, a broadcast of the packet is perform. And it is the resposibility of the NIC Driver (NDIS) to validate the packet as belonging to that particular system.
Note: This application I'm working on is more than likely reside within an Intranet.
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Sirs,
the below is not an explicite MFC question, and answer would help me anyway.
My hard disk c:\ is partitioned and I would be pleased to get rid of it?
Accidentially, don't you know how?
Thank you for your help in advance.
Bunburry
A subject that is beautiful in itself gives no suggestion to the Artist. It lacks imperfection. (O.Wilde)
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A hard drive cannot be accidentally partitioned. To remove a partition you'll need software like Partition Magic.
Christian
As I learn the innermost secrets of the around me, they reward me in many ways to keep quiet.
Men with pierced ears are better prepared for marriage. They've experienced pain and bought Jewellery.
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Yes, PM allows you to create, size and remove partitions. It is also a boot manager ( I have Windows XP, 2000 and 98 all on one HDD ).
Christian
As I learn the innermost secrets of the around me, they reward me in many ways to keep quiet.
Men with pierced ears are better prepared for marriage. They've experienced pain and bought Jewellery.
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Well if you're looking into getting rid of it and you have a Win 9x system have you tried "fdisk"? Just thought I would my two cents 
Sam C
----
Systems Manager
Hospitality Marketing Associates
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I have no problem obtaining the MAC address of a client, given the IP of the client.
IP Helper API under Windows 2k allow the retrieval of the MAC address given the
IP address.
The question I'm having is, if the IP of the client is not given, and only its MAC address is known. Can Winsock send a packet to the client based on the client's MAC address? Likewise, can the client listen for this packet?
I am currently looking into NDIS for possible solution, but hopefully there is an easier solution than NDIS.
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The only way I am aware of to do MAC to IP would be if you could some how access a routers ARP table...
Probably didn't help any.
Rob
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Sorry for not clearly specifying my problem.
I need to communicate MAC between client and server.
By this I mean, to send a packet from the client to
the server (or vice versa) using ONLY a MAC address.
It seems to me that since the bottom layer of the OSI model
talks ARP, it is evident that Winsock communicate ARP
at a some stage. As such, further investigation leads
me to NDIS. Which is 2 layers below TCP/IP and UDP.
It is at this level that I am hitting the break wall.
Any solution you can offer at either the Winsock level
or the NDIS level would be great.
Thanks in advance for the help.
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Hi all!
I use appWizard to make a dialog base program. the default icon for my program will then be the MFC icon. I have a nice (32 X 32) icon file, and want to use it instead. the problem is when I imported this icon into the resource, the size becomes 16 X 16. This make the picture look very ugly. Besides this problem, was another one. What I did to change the icon was I changed the line:
//m_hIcon = AfxGetApp()->LoadIcon(IDR_MAINFRAME);
with this line bellow:
m_hIcon = AfxGetApp()->LoadIcon(IDI_MY_LOGO);
after doing this, my icon was still not visible. I had to delete the MFC icon from the resource to make mine work.
Can someone please tell me how to change icon the proper way and how to load 32X32 icons
Thank you very much
Vu
vucsuf
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I tend to use the resource editor and clear out the contents of the IDR_MAINFRAME image and then paste my icon into IDR_MAINFRAME. Saves a lot of hassle,
Michael 
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Try this Code
HICON hIcon;
LPCTSTR lpIconName;
lpIconName = MAKEINTRESOURCE(IDI_MY_LOGO);
hIcon = ::LoadIcon(AfxFindResourceHandle(lpIconName, RT_GROUP_ICON), lpIconName);
GetActiveWindow()->SetIcon(hIcon, TRUE);
Remember:
LoadIcon can only load an icon whose size conforms to the SM_CXICON and SM_CYICON system metric values. Use the LoadImage function to load icons of other sizes.
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hi, ok my question is the following:
i have a win32 project in Visual C++ and i'm not using mfc whatsoever. Lets say i created a dialog window from a resource file, so it displays a window on the screen, still pure win32. Now if i go to the classwizard and i click "add new" i can add a new class based on another class. I pick CAsyncSocket as the base class and it adds the class to my win32 project. If i try to compile now i keep getting "Base Class Undefined" and it adds a line to the cpp file of the SocketClass "#include "script1.h" but that file doesn't exist.
Is this because you can't use the CAsyncSocket class without mfc or do i have to change some things to make it work?
Thanks for your time
Kuniva
Want, take, have.
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CAsyncSocket is part of MFC. you'd need to include MFC include files, and link to MFC libs, and enable "use MFC" in your project.
Sorry to dissapoint you all with my lack of a witty or poignant signature.
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We make a device which currently connects to the COM ports.
However of late I see COM ports are to be abolished mid-next year.
Does anyone have any info on programming USB???
I see there are hardware converters available to convert COM->USB.
What exactly do these do? Surely software written to address a COM port cannot access a USB in the same manner - so the adaptor is rendered useless???
--
The Obliterator
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Actually yeah it does, thanks.
The MS DDK looks promising, though I feel I have a lot of work ahead of me! 
Damn our customers and these ever changing standards!
I'd seen usb.org but it seemed more orientated to the technical specification rather than what I was after.
--
The Obliterator
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Don't ignore Firewire. It's faster than USB and is great for hanging multiple storage devices off a single machine.
1294a was just completed, doubling the speed of Firewire to 960mb.
I believe USB2 is only 400mb or so. Is that correct?
To hell with those thin-skinned pillow-biters. - Me, 10/03/2001
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Yeah, one customer has requested Firewire support... but as its not really supplied as standard on any PCs I would be very reluctant.
Besides I really don't see the need, our device is very low bandwidth (2 bytes every 38ms!)
Unless there are other advantages to Firewire???
Thanks anyhow though.
--
The Obliterator
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You mean beyond the fact that it always seems to be significantly faster than USB, or that the standard has been around long enough to be a mature spec, or the fact that you can plug your IDE drives (hard drives, CR-ROMs, CD-R/W's and DVD) into external firewire cases?
Nope, no other benefits...
To hell with those thin-skinned pillow-biters. - Me, 10/03/2001
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>>you can plug your IDE drives (hard drives, CR-ROMs, CD-R/W's and DVD) into external firewire cases?
Is this not the same for USB also??
I agree with the maturity and speed points though.
Problem is I need a solution thats widely available, that people can connect to their laptops, etc. USB seems to fit my needs about the best.
--
The Obliterator
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By design, USB has a cable length limit of 5 metres.
You are able to use up to 4 cables extenders to increase the distance to 25 metres, but no futher. So if your device is located more than 25 metres from your computer, USB is not the way to go. As far as I know, Firewire does not have this cable length problem.
My advise is to read the USB specification carefully and make sure the USB is the solution for your device, it does have some very important limitations.
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Thankyou, this was not an issue I was aware of. Though that should be more than adequate for our device.
I have downloaded volumes on the USB specification and look forward to a little light reading!
--
The Obliterator
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>> However of late I see COM ports are to be abolished mid-next year
Funniest thing i've heard all day.
Admittedly, today has been a bit slow. But that's utter chud anyway. People still use COM ports for Modems and stuff. And serial connections to telco apparatus. And most POS equipment is RS-232 (tils, receipt printers, barcode readers etc)
Sorry to dissapoint you all with my lack of a witty or poignant signature.
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Well, I hate to be the bearer of bad news, but Intel has publicly stated that they're going to abandon of "legacy device" support within the next year or so. This means bye bye to serial ports, parallel ports, PS/2 mouse ports, keyboard ports, etc.
I guess they want to throw everything onto the USB bus. It would certainly make for more efficient chipsets, but it would also force everyone to update their admittedly aging array of legacy devices. If Intel abandons these ports, you can most assuredly count on Microsoft following suit in subsequent versions of Windows.
To hell with those thin-skinned pillow-biters. - Me, 10/03/2001
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COM ports will be around a LONG LONG LONG LONG time. Might not be available on your standard PC system, but you will always be able to get them as addons.
Too much stuff needs a COM port.
Tim Smith
Descartes Systems Sciences, Inc.
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