[libusb] linux: permission denied opening USB device

[Bob S. <bo...@gm...>]

I'm getting the following error whe I try to open a USB ANT stick, vendor =
0fcf, product = 1008.

libusb: error [_get_usbfs_fd] libusb couldn't open USB device
/dev/bus/usb/003/026: Permission denied
libusb: error [_get_usbfs_fd] libusb requires write access to USB device
nodes.

I think that this worked a few weeks ago. I was working on the Windows
version of my application, then came back
to the linux version to test it and now I get this. What is the best way to
fix this? This is on Ubuntu 14.04.

Summary of the libusb calls minus error checking code:

libusb_init(&ctx);
libusb_set_debug(ctx, 3);
libusb_get_version();

n = libusb_get_device_list(ctx, &list);

for(k=0; k<n; k++){
   libusb_device_descriptor desc = {0};
   libusb_device *device;
   device = list[k];

   status = libusb_get_device_descriptor(device, &desc);
   config = NULL;
   status = libusb_get_config_descriptor(device, 0, &config);

   if (config->bNumInterfaces==0)  {
      libusb_free_config_descriptor(config);
      config = NULL;
      continue;
   }

   if (desc.idVendor == 0x0fcf && desc.idProduct == 1008)) {
      libusb_device_handle *handle = NULL;

      status = libusb_open(device, &handle);
      switch(status)  {
         case 0:
            break;
         case LIBUSB_ERROR_NO_MEM:
            break;
         case LIBUSB_ERROR_ACCESS:  // <<<<<<<<<<<<< user has insufficient
permissions **** FAILS HERE ****
            break;
         case LIBUSB_ERROR_NO_DEVICE:
            break;
         default:
            break;
      }
   }