Function nginx::SSL_select_next_proto

pub unsafe extern "C" fn SSL_select_next_proto(
    out: *mut *mut c_uchar, 
    outlen: *mut c_uchar, 
    in_: *const c_uchar, 
    inlen: c_uint, 
    client: *const c_uchar, 
    client_len: c_uint
) -> c_int