#include <libnbd.h> int nbd_connect_tcp ( struct nbd_handle *h, const char *hostname, const char *port );
Connect (synchronously) to the NBD server listening on
port may be a port name such as
"nbd", or it may be a port number as a string such as
This call returns when the connection has been made. By default, this proceeds all the way to transmission phase, but nbd_set_opt_mode(3) can be used for manual control over option negotiation performed before transmission phase.
If the call is successful the function returns
-1 is returned.
Refer to "ERROR HANDLING" in libnbd(3) for how to get further details of the error.
The following parameters must not be NULL:
port. For more information see "Non-NULL parameters" in libnbd(3).
nbd_connect_tcp can be called when the handle is in the following state:
┌─────────────────────────────────────┬─────────────────────────┐ │ Handle created, before connecting │ ✅ allowed │ │ Connecting │ ❌ error │ │ Connecting & handshaking (opt_mode) │ ❌ error │ │ Connected to the server │ ❌ error │ │ Connection shut down │ ❌ error │ │ Handle dead │ ❌ error │ └─────────────────────────────────────┴─────────────────────────┘
This function first appeared in libnbd 1.0.
If you need to test if this function is available at compile time check if the following macro is defined:
#define LIBNBD_HAVE_NBD_CONNECT_TCP 1
nbd_aio_connect_tcp(3), nbd_create(3), nbd_set_opt_mode(3), libnbd(3).
Richard W.M. Jones
Copyright Red Hat
This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
libnbd(3), libnbd-release-notes-1.2(1), NBD(3), nbd_aio_connect_tcp(3), nbd_connect_uri(3), nbdfuse(1), nbdublk(1).