Function PEM_read_bio_PUBKEY_ex 

pub unsafe extern "C" fn PEM_read_bio_PUBKEY_ex(
    out: *mut BIO,
    x: *mut *mut EVP_PKEY,
    cb: pem_password_cb,
    u: *mut c_void,
    libctx: *mut OSSL_LIB_CTX,
    propq: *const c_char,
) -> *mut EVP_PKEY