I’m a little lost on the usefulness of configuring an OpenSSL memory BIO (BIO_s_mem()) in non-blocking mode, I imagine that it has a use but I’m not sure I see it.

i need set client-server session. How to extract certificate for app android from pfx format? Do need only root certificate? I am set root certificate pem format because der don’t set, but i get faild handshake.
The certificate and key are installed on the server

I have to give an OpenSSL-command the parameter CAfile with multiple certificates included.
Need it for s_client a TLS-connection.

I’m trying to perform docker login (into a private company’s server) but can’t solve a connectivity issue that appears on every attempt.