NAME
SSL_get_fd — get file descriptor linked to an SSL object
Synopsis
#include <openssl/ssl.h> 
int
SSL_get_fd(SSL *ssl); 
int SSL_get_rfd(SSL *ssl); 
int
SSL_get_wfd(SSL *ssl);
DESCRIPTION
SSL_get_fd() returns the file descriptor which is linked to
ssl. SSL_get_rfd() and SSL_get_wfd() return the file descriptors
for the read or the write channel, which can be different. If the
read and the write channel are different, SSL_get_fd() will return
the file descriptor of the read channel. 
RETURN VALUES
The following return values can occur: 
-1
The operation failed, because the underlying BIO is not of
the correct type (suitable for file descriptors). 
>=0
The file descriptor linked to ssl. 
SEE ALSO
SSL_set_fd(3), ssl(3) , bio(3)