=pod

=head1 NAME

SSL_set_fd, SSL_set_rfd, SSL_set_wfd - connect the SSL object with a file descriptor

=head1 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);

=head1 DESCRIPTION

SSL_set_fd() sets the file descriptor B<fd> as the input/output facility
for the TLS/SSL (encrypted) side of B<ssl>. B<fd> will typically be the
socket file descriptor of a network connection.

When performing the operation, a B<socket BIO> is automatically created to
interface between the B<ssl> and B<fd>. The BIO and hence the SSL engine
inherit the behaviour of B<fd>. If B<fd> is non-blocking, the B<ssl> will
also have non-blocking behaviour.

If there was already a BIO connected to B<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.

=head1 RETURN VALUES

The following return values can occur:

=over 4

=item Z<>0

The operation failed. Check the error stack to find out why.

=item Z<>1

The operation succeeded.

=back

=head1 SEE ALSO

L<SSL_get_fd(3)>, L<SSL_set_bio(3)>,
L<SSL_connect(3)>, L<SSL_accept(3)>,
L<SSL_shutdown(3)>, L<ssl(3)> , L<bio(3)>

=cut
