nbd_connect_tcp - connect to NBD server over a TCP port
Contents
Copyright
Copyright Red Hat
Description
Connect (synchronously) to the NBD server listening on "hostname:port". The "port" may be a port name
such as "nbd", or it may be a port number as a string such as "10809".
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.
Errors
On error -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: "h", "hostname", "port". For more information see "Non-NULL
parameters" in libnbd(3).
Handle State
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 │
└─────────────────────────────────────┴─────────────────────────┘
License
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-1.22.2 2025-06-16 nbd_connect_tcp(3)
Name
nbd_connect_tcp - connect to NBD server over a TCP port
Return Value
If the call is successful the function returns 0.
See Also
nbd_aio_connect_tcp(3), nbd_create(3), nbd_set_opt_mode(3), libnbd(3).
Synopsis
#include <libnbd.h>
int nbd_connect_tcp (
struct nbd_handle *h, const char *hostname,
const char *port
);
Version
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
