NAME
nbd_get_uri - construct an NBD URI for a connection
SYNOPSIS
#include
<libnbd.h>
char * nbd_get_uri (
struct nbd_handle *h
);
DESCRIPTION
This makes a best effort attempt to construct an NBD URI which could be used to connect back to the same server (using nbd_connect_uri(3)).
In some cases there is not enough information in the handle to successfully create a URI (eg. if you connected with nbd_connect_socket(3)). In such cases the call returns "NULL" and further diagnostic information is available via nbd_get_errno(3) and nbd_get_error(3) as usual.
Even if a URI is returned it is not guaranteed to work, and it may not be optimal.
nbdinfo(1) --uri option is a way to access this API from shell scripts.
RETURN VALUE
This call returns a string. The caller must free the returned string to avoid a memory leak.
ERRORS
On error "NULL" 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_get_uri can be called when the handle is in the following states:
┌─────────────────────────────────────┬─────────────────────────┐
│ Handle created, before connecting │ ❌
error │
│ Connecting │ ✅ allowed │
│ Connecting & handshaking (opt_mode) │
✅ allowed │
│ Connected to the server │ ✅ allowed
│
│ Connection shut down │ ✅ allowed │
│ Handle dead │ ✅ allowed │
└─────────────────────────────────────┴─────────────────────────┘
VERSION
This function first appeared in libnbd 1.8.
If you need to test if this function is available at compile time check if the following macro is defined:
#define LIBNBD_HAVE_NBD_GET_URI 1
SEE ALSO
nbd_aio_connect_uri(3), nbd_connect_socket(3), nbd_connect_uri(3), nbd_create(3), nbd_get_errno(3), nbd_get_error(3), nbd_supports_uri(3), libnbd(3), nbdinfo(1).
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