// Initialize libusb libusb_init(&ctx);
No examination is complete without acknowledging libusb’s weaknesses. First, is notoriously opaque. Many functions return negative error codes ( -1 , -4 , -12 ) that map to LIBUSB_ERROR_IO , LIBUSB_ERROR_NO_MEM , etc., but the library provides no per-transfer string descriptions. Debugging failed transfers often requires enabling verbose logging and interpreting kernel messages. libusb driver
// Release the interface and close the device libusb_release_interface(handle, 0); libusb_close(handle); // Initialize libusb libusb_init(&ctx)
// Read from the device unsigned char read_buffer[1024]; int transferred; libusb_bulk_transfer(handle, 0x02, read_buffer, sizeof(read_buffer), &transferred, 0); -12 ) that map to LIBUSB_ERROR_IO