pub unsafe extern "C" fn CPXsetdeletenodecallbackfunc(
env: CPXENVptr,
deletecallback: Option<unsafe extern "C" fn(xenv: CPXCENVptr, wherefrom: c_int, cbhandle: *mut c_void, seqnum: c_int, handle: *mut c_void)>,
cbhandle: *mut c_void,
) -> c_int