nbd_connect_socket(3) LIBNBD nbd_connect_socket(3)

nbd_connect_socket - connect directly to a connected socket

#include <libnbd.h>
int nbd_connect_socket (
      struct nbd_handle *h, int sock
    );

Pass a connected socket "sock" through which libnbd will talk to the NBD server.

The caller is responsible for creating and connecting this socket by some method, before passing it to libnbd.

If this call returns without error then socket ownership is passed to libnbd. Libnbd will close the socket when the handle is closed. The caller must not use the socket in any way.

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 0.

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". For more information see "Non-NULL parameters" in libnbd(3).

nbd_connect_socket 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 1.2.

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_SOCKET 1

nbd_aio_connect_socket(3), nbd_connect_command(3), nbd_create(3), nbd_set_opt_mode(3), libnbd(3), socket(7).

Eric Blake

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

2024-05-31 libnbd-1.20.0