Function EN_getnodeid 

pub unsafe extern "C" fn EN_getnodeid(
    ph: EN_Project,
    index: c_int,
    out_id: *mut c_char,
) -> c_int

@brief Gets the ID name of a node given its index. @param ph an EPANET project handle. @param index a node’s index (starting from 1). @param[out] out_id the node’s ID name. @return an error code

The ID name must be sized to hold at least @ref EN_SizeLimits “EN_MAXID+1” characters.