Constant openssl_sys::OPENSSL_VERSION
pub const OPENSSL_VERSION: c_int = 0;
The portability is definied by:
#[cfg(all(any(ossl110, libressl271), not(any())))]
pub const OPENSSL_VERSION: c_int = 0;
#[cfg(all(any(ossl110, libressl271), not(any())))]