SSL_set_fd - connect the SSL object with a file descriptor
Synopsis #include <openssl/ssl.h> int
SSL_set_fd(SSL *ssl, int fd); int SSL_set_rfd(SSL *ssl,
int fd); int SSL_set_wfd(SSL *ssl, int fd);
DESCRIPTIONSSL_set_fd() sets the file descriptor fd as the input/output
facility for the TLS/SSL (encrypted) side of ssl. fd will typically
be the socket file descriptor of a network connection.
When performing the operation, a socket BIO is automatically
created to interface between the ssl and fd. The BIO and hence the
SSL engine inherit the behaviour of fd. If fd is non-blocking, the
ssl will also have non-blocking behaviour.
If there was already a BIO connected to ssl , BIO_free() will
be called (for both the reading and writing side, if different).
SSL_set_rfd() and SSL_set_wfd() perform the respective action,
but only for the read channel or the write channel, which can be
set independently.
RETURN VALUESThe following return values can occur:
0 The operation failed. Check the error stack to find out why.
HP Open Source Security for OpenVMS Volume 2:... 
SSL Application Programming Interface (API) Reference
