Name
v4l2_ctrl_handler_log_status — 
     Log all controls owned by the handler.
 
Arguments
- hdl
- 
     The control handler.
     
- prefix
- 
     The prefix to use when logging the control values. If the
     prefix does not end with a space, then “: ” will be added
     after the prefix. If - prefix== NULL, then no prefix will be
     used.
 
Description
   For use with VIDIOC_LOG_STATUS.
   
   Does nothing if hdl == NULL.