pub unsafe extern "C" fn CPXsetheuristiccallbackfunc(
env: CPXENVptr,
heuristiccallback: Option<unsafe extern "C" fn(xenv: CPXCENVptr, cbdata: *mut c_void, wherefrom: c_int, cbhandle: *mut c_void, objval_p: *mut f64, x: *mut f64, checkfeas_p: *mut c_int, useraction_p: *mut c_int) -> c_int>,
cbhandle: *mut c_void,
) -> c_int