Function mmal_sys::mmal_port_parameter_get

pub unsafe extern "C" fn mmal_port_parameter_get(
    port: *mut MMAL_PORT_T, 
    param: *mut MMAL_PARAMETER_HEADER_T
) -> Type

Get a parameter from a port. The size field must be set on input to the maximum size of the parameter (including the header) and will be set on output to the actual size of the parameter retrieved.

\note If MMAL_ENOSPC is returned, the parameter is larger than the size given. The given parameter will have been filled up to its size and then the size field set to the full parameter's size. This can be used to resize the parameter buffer so that a second call should succeed.

@param port The port to which the request is sent. @param param The pointer to the header of the parameter to get. @return MMAL_SUCCESS on success