-int usbtmc_sendscpi(usb_dev_handle *dev, char* cmd, unsigned char *resp, int resplen);
-usb_dev_handle* usbtmc_initscope(void);
-void usbtmc_close(usb_dev_handle *sc);
-void usbtmc_claim(usb_dev_handle *sc);
-void usbtmc_release(usb_dev_handle *sc);
+int usbtmc_sendscpi(struct usb_dev_handle *dev, char* cmd, unsigned char *resp, int resplen);
+struct usb_dev_handle* usbtmc_initscope(void);
+void usbtmc_close(struct usb_dev_handle *sc);
+void usbtmc_claim(struct usb_dev_handle *sc);
+void usbtmc_release(struct usb_dev_handle *sc);