send a full frame containing only zeroes instead of a zero-byte frame

diff --git a/hmcfgusb.c b/hmcfgusb.c
index d08641935f41f0f9d84d1079bcb4edd047bcc01d..d8a442f690a04bba9d368c4c4340b54311e2e64b 100644 (file)
--- a/hmcfgusb.c
+++ b/hmcfgusb.c
@@ -146,8 +146,11 @@ int hmcfgusb_send_null_frame(struct hmcfgusb_dev *usbdev, int silent)
 {
        int err;
        int cnt;
+       unsigned char out[0x40];
 
-       err = libusb_interrupt_transfer(usbdev->usb_devh, EP_OUT, NULL, 0, &cnt, USB_TIMEOUT);
+       memset(out, 0, sizeof(out));
+
+       err = libusb_interrupt_transfer(usbdev->usb_devh, EP_OUT, out, sizeof(out), &cnt, USB_TIMEOUT);
        if (err && (!silent)) {
                fprintf(stderr, "Can't send null frame: %s\n", usb_strerror(err));
                return 0;