Help needed in C

I am a starter in C. I am doing a Project to on GPS. I have to connect GPS to my Laptop but the Laptop doesnot have serial port and hence i have to use USB-Serial adapter to connect to GPS. The connection gives COM12 port in device manager. The problem is how to get the GPS string in C. I tried certain to codes to open the port in C but they dont work. Also guide me whether it is possible to copy part of char string to int string using strncpy(). Thanks

This looks like it might be complicated to sort out, and probably impossible unless you can post more details. Can you show what code you have tried, or give more detail about what exactly you are trying when you say "code to open the port but they don't work"?

Do you have some documentation about your gps device that tells you how to communicate with it? Maybe it needs some magic dance before it will talk back.

Also, It is possible to convert chars to ints using atoi() (among other methods).

Have you tried looking on Google for this? I found this on the first page of "c serial port programming" results, so you might try that, or if it's not completely helpful, some version of that...

Also, look on the website for the GPS manufacturer of your device. They might have resources for developers to use. API documentation or additional documentation. If the GPS driver assumes that it will be a serial com port in the range of COM1-4 then it might not be possible to tell the driver to look at COM12. It depends on the way the driver is implemented.

Also it would be nice to know on what platform you wish to do this. Windows, Mac, Linux? You mention that it uses a COM port, this would be Windows, but are you trying to use it with Windows?

On Linux you can write code to the libusb package which will do most of the work for you. Then all you would need to do is convert the data coming and going from your device to the format needed in this library. What you are really doing here is writing a device driver regardless of the platform.

Another thing to think about is how will you connect the device to your computer. You mentioned that there is no serial port on your computer, is there also a USB port on your device?