i install LibUSB-Win32 and trying basic usb program :

include <stdio.h>

include <usb.h>

include <libusb.h>

int main(void)
{
struct usb_bus busses;
struct usb_bus bus;

usb_init();
usb_find_busses();
usb_find_devices();

busses = usb_get_busses();
for (bus = busses; bus; bus = bus->next) {
    struct usb_device *dev;
    for (dev = bus->devices; dev; dev = dev->next) {
        printf("%04x:%04x\n",
            dev->descriptor.idVendor, dev->descriptor.idProduct);
    }
}
return 0;

}

but i have error messages :
[Linker error] undefined reference to usb_init' [Linker error] undefined reference tousb_find_busses'
[Linker error] undefined reference to usb_find_devices' [Linker error] undefined reference tousb_get_busses'

what can i do?
thanks . .

You have to link the right library. If you go to project->options and choose add library ( or something similar, it has been a few years since I used Dev-C ) it should work. The library to add is probably found in where you installed Dev-C under /include. Sorry I seem cryptic but obviously I don't know YOUR system setup. It may be ( for example ) c:/program/Dev-C/mingw32/include... there you'll probably find a file named libusb.o or libusb.a. That's the library to include. Hope this help you at least get started on the search.