Function qmap_get 

pub unsafe extern "C" fn qmap_get(
    hd: u32,
    key: *const c_void,
) -> *const c_void

@brief Retrieve a value by key.

For maps with QM_MULTIVALUE flag, this returns the FIRST matching value only. To retrieve all values for a key, use qmap_get_multi() instead.

@param[in] hd Map handle. @param[in] key Key to look up. @return Pointer to value or NULL if not found. For QM_MULTIVALUE maps, returns first match. See qmap_common for pointer ownership rules.