ders must end with an implementation that produces that output type.</p>

<p>At the beginning of the encoding process, a constructor provided by the caller is called to ensure that there is an appropriate provider-side object to start with. The constructor is set with OSSL_ENCODER_CTX_set_construct().</p>

<p><b>OSSL_ENCODER_INSTANCE</b> is an opaque structure that contains data about the encoder that is going to be used, and that may be useful for the constructor. There are some functions to extract data f