Determine the current alternate interface.
int32_t UsbGetAltInterface( 
    int32_t udev, 
    uint8_t *altnum
);
Parameters
udev 
- Device handle from UsbOpenDevice. 
 altnum 
- Pointer to a variable to receive the current alternate interface ID.   
 
Return Values
| USB_ERR_NORMAL_COMPLETION | 
Success. | 
| USB_ERR_NO_STACK | 
The USB stack is not ready. | 
| USB_ERR_MEMORY | 
Memory could not be allocated for the operation. | 
| USB_ERR_TIMEOUT | 
The device did not respond. | 
Requirements
| Versions | 
Defined in | 
Include | 
Link to | 
| INtime 5.0 | 
intime/rt/include/usbif3h | 
usbif3h | 
usbif3lib |