Function mmal_sys::mmal_port_parameter_alloc_get

pub unsafe extern "C" fn mmal_port_parameter_alloc_get(
    port: *mut MMAL_PORT_T, 
    id: u32, 
    size: u32, 
    status: *mut Type
) -> *mut MMAL_PARAMETER_HEADER_T

Get a parameter from a port allocating the required amount of memory for the parameter (i.e. for variable length parameters like URI or arrays). The size field will be set on output to the actual size of the parameter allocated and retrieved.

The pointer returned must be released by a call to \ref mmal_port_parameter_free().

@param port port to send request to @param id parameter id @param size initial size hint for allocation (can be 0) @param status status of the parameter get operation (can be 0) @return pointer to the header of the parameter or NULL on failure.