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I have a terminal program that allows user authentication by barcode scanner or keyboard input. Need to disable keyboard input functionality. But scanner is keyboard wedged, so it also stopped working when keyboard is disabled.
Suggest any way or code to do it.
Thanking you all. - Ravi 
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Hi, you could try this:
1. keep the keyboard enabled
2. teach your scanner to prefix and append specific constant string delimiters (say "<<<" and ">>>")
3. upon data input reject everything that isn't inside said delimiters.
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Thanks Luc,
But I don't have the source-codes of existing program, and also the program is one of the terminal module of ERP system. So i cant modify the existing application. I have to write a new program that simulates with the existing program, But I am not getting any idea to implement it.
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you might still be able to apply ny idea from outside the app by installing a global keyboard hook (see some articles on CP). I suggest you make a little utility to do so, and keep it accessible in the system tray, so you can re-enable keyboard processing when things would go wrong.
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Thanks again.
I think it will completely disable the keyboard, but in my case user have to do some entries in the program after getting logged in by scanner. So how could I synchronize my external application with the existing application, so that it will enable the keyboard after scanner scanned the barcode and authorize the user. And also how could I disable the keyboard again when user finished his work and logged out (Log out is based on Y/N confirmation message).
Is any way to do it.
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I used to work on those things in a retail store, and I doubt that there's a way to do it with your current setup. The wedge is simply a term used in the industry that means "we wired two serial devices in parallel so we wouldn't need a separate jack." That's literally how they're wired! The computer (or terminal) has no way to tell which device is sending data. The only suggestion I can make is to select a special character to insert in your authentication barcode which the scanner can produce, but the keyboard can't.
For instance, very few people remember that ctrl-G was used to ring the bell on a remote teletype, and DOS-based PCs kept it to beep the internal speaker. But nothing in Windows uses it, and there's no reason you can't make a scanner read it, if you have a barcode format selected that allows the full ASCII character set. You might use it as a delimiter between the username and password, for instance. Nobody would think of trying to manually type that today.
"A Journey of a Thousand Rest Stops Begins with a Single Movement"
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Thanks Mr. Wright, but then how could I merge this logic with my existing application, because I don't have source-codes. Or I create separate program that detects every input, of the system, then distinguish scanner and keyboard inputs on the basis of special characters. Is it possible.
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Yes, it is possible, but I'm not a good enough programmer to tell you how to do it. Maybe someday...
Since you can't change the existing program, you need to create a keyboard hook that intercepts inputs from the keyboard port before your existing program gets them, process the data, then pass it on to the usual handler. I believe there are articles on CodeProject that describe how to do that, but I'm not smart enough yet to help. The method I suggested may not be the best way to do it, but my point was that Windows does not have a way to tell where the input is coming from; you need to provide some distinguishing feature that you can grab and process. Whatever you can do to make the scanner input look different from a regular keyboard input will do the job. All you need to do is catch it and process it.
Search the articles here, and I think you'll find an answer. I look forward to reading the article you write about the solution one day soon. And, by the way, I'm Roger to my friends, not Mr. Wright, and I consider all my associates at CodeProject friends. Welcome to the neighborhood, Ravi. 
"A Journey of a Thousand Rest Stops Begins with a Single Movement"
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Thanks Roger, I will definitely try this, and let you know.
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You're welcome, and be sure to check Dan Neely's response below. H provided two excellent references.
"A Journey of a Thousand Rest Stops Begins with a Single Movement"
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Good references, Dan!
"A Journey of a Thousand Rest Stops Begins with a Single Movement"
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Please help....
I use RASAPI32.RasEnumDevices to determine which RAS devices (ISDN or Modems) by name and type are connected to my computer. I use System.IO.Ports.SerialPorts to list all of my COM ports which also shows if a modem device is connected. I use these devices in connecting to the internet. The phonebook entry for the device is created on-the-fly.
What I need now is to put it together. How or where can I find out in WIN XP which RAS Device name is on which port. I need the port for issuing AT commands. I use an analog modem, an ISDN FRitz Card and a UTMS modem card.
WMI.POTSmodem does not list any of these devices.
Coding is in C#.
Ralph
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Hi,
I don't know if it is the right place to ask this question, if it a'int kindly guide me to the right place.
Problem:
I have a Live raw video feed from a camera connected to a video capture card which doesn't support hardware based video compression, so i wish to use some software based compression technique.
I have an nvidia Graphic Card (8400 GT). I wish to inquire whether there is any video codec currently available which i can use to do a Live GPU based encoding of the raw video feed. And does ffdshow currently supports GPU based encoding.
Any help will be greatly appreciated.
Thank you...
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Hi,
I want to ask where to get a wireless device to have a hotsport just like the one they use in costa coffee and other coffee shop where you buy and then they will print a receipt contains user ID and password which allows you connect to the internet?
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I have also seen the same in some hotels like sheraton?
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Try a wireless hotspot shop.
Morality is indistinguishable from social proscription
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I want to ask what operating system runs on ATM?
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Again, anything you want... Linux, Windows NT or better, ... They are just PC's with custom hardware...
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I want to ask what operating system runs on Kiosks?
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Again, anything you want... Linux, Windows NT or better, ... They are just PC's with custom hardware...
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I want to ask what programming language they use for ATM?
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Same answer as before... anything you want.
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I want to ask what programming language they use for Kiosk?
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Depends a bit on the application, but there is no one langauge used for any app in a kiosk environment. You can use anything you want.
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