nbd_connect_vsock(3)                LIBNBD                nbd_connect_vsock(3)


NAME
       nbd_connect_vsock - connect to NBD server over AF_VSOCK protocol

SYNOPSIS
        #include <libnbd.h>

        int nbd_connect_vsock (
              struct nbd_handle *h, uint32_t cid, uint32_t port
            );

DESCRIPTION
       Connect (synchronously) over the "AF_VSOCK" protocol from a virtual
       machine to an NBD server, usually running on the host.  The "cid" and
       "port" parameters specify the server address.  Usually "cid" should be
       2 (to connect to the host), and "port" might be 10809 or another port
       number assigned to you by the host administrator.

       Not all systems support "AF_VSOCK"; to determine if libnbd was built on
       a system with vsock support, see nbd_supports_vsock(3).

       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.

RETURN VALUE
       If the call is successful the function returns 0.

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

HANDLE STATE
       nbd_connect_vsock 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                |
        <?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?>

VERSION
       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_VSOCK 1

SEE ALSO
       nbd_aio_connect_vsock(3), nbd_create(3), nbd_set_opt_mode(3),
       nbd_supports_vsock(3), libnbd(3).

AUTHORS
       Eric Blake

       Richard W.M. Jones

COPYRIGHT
       Copyright Red Hat

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-1.20.0                     2024-05-31              nbd_connect_vsock(3)