Constant openssl_sys::SSL_OP_NO_DTLSv1
pub const SSL_OP_NO_DTLSv1: c_ulong = 0x04000000;
The portability is definied by:
#[cfg(all(ossl102, not(any())))]
pub const SSL_OP_NO_DTLSv1: c_ulong = 0x04000000;
#[cfg(all(ossl102, not(any())))]