This function also frees public key resources as received with openssl_pkey_get_public().
Manual above should say: "Frees a pkey resource"
(PHP 4 >= 4.2.0, PHP 5, PHP 7, PHP 8)
openssl_pkey_free — Libera una clave privada
Esta función libera una clave privada creada por openssl_pkey_new().
keyUn recurso que contiene la clave.
No devuelve ningún valor.
This function also frees public key resources as received with openssl_pkey_get_public().
Manual above should say: "Frees a pkey resource"PHP 8 deprecates openssl_free_key (actually openssl_pkey_free which it aliases) and automatically destroys the key instance when it goes out of scope.