osx man page for ssl_get_fd

SSL_get_fd(3)							      OpenSSL							     SSL_get_fd(3)

NAME
       SSL_get_fd - get file descriptor linked to an SSL object

SYNOPSIS
	#include <openssl/ssl.h>

	int SSL_get_fd(const SSL *ssl);
	int SSL_get_rfd(const SSL *ssl);
	int SSL_get_wfd(const 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)

50								    2013-03-05							     SSL_get_fd(3)