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nbd_aio_connect_uri - Man Page

connect to an NBD URI


 #include <libnbd.h>

 int nbd_aio_connect_uri (
       struct nbd_handle *h, const char *uri


Begin connecting to the NBD URI uri.  Parameters behave as documented in nbd_connect_uri(3).

You can check if the connection attempt is still underway by calling nbd_aio_is_connecting(3).  If nbd_set_opt_mode(3) is enabled, the connection is ready for manual option negotiation once nbd_aio_is_negotiating(3) returns true; otherwise, the connection attempt will include the NBD handshake, and is ready for use once nbd_aio_is_ready(3) returns true.

Return Value

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

Handle State

nbd_aio_connect_uri 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:


See Also

nbd_aio_is_connecting(3), nbd_aio_is_negotiating(3), nbd_aio_is_ready(3), nbd_connect_uri(3), nbd_create(3), nbd_set_opt_mode(3), libnbd(3), https://github.com/NetworkBlockDevice/nbd/blob/master/doc/uri.md.


Eric Blake

Richard W.M. Jones


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

Referenced By

libnbd(3), NBD(3), nbd_connect_uri(3), nbd_get_uri(3), nbd_supports_uri(3).

2024-06-25 libnbd-1.21.1