NAME

nbd_set_full_info - control whether NBD_OPT_GO requests extra details

SYNOPSIS

 #include <libnbd.h>

 int nbd_set_full_info (
       struct nbd_handle *h, bool request
     );

DESCRIPTION

By default, when connecting to an export, libnbd only requests the details it needs to service data operations. The NBD protocol says that a server can supply optional information, such as a canonical name of the export (see nbd_get_canonical_export_name(3)) or a description of the export (see nbd_get_export_description(3)), but that a hint from the client makes it more likely for this extra information to be provided. This function controls whether libnbd will provide that hint.

Note that even when full info is requested, the server is not obligated to reply with all information that libnbd requested. Similarly, libnbd will ignore any optional server information that libnbd has not yet been taught to recognize. Furthermore, the hint to request block sizes is independently controlled via nbd_set_request_block_size(3).

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_set_full_info can be called when the handle is in the following states:

 ┌─────────────────────────────────────┬─────────────────────────┐
 │ Handle created, before connecting   │ ✅ allowed              │
 │ Connecting                          │ ❌ error                │
 │ Connecting & handshaking (opt_mode) │ ✅ allowed              │
 │ Connected to the server             │ ❌ error                │
 │ Connection shut down                │ ❌ error                │
 │ Handle dead                         │ ❌ error                │
 └─────────────────────────────────────┴─────────────────────────┘

VERSION

This function first appeared in libnbd 1.4.

If you need to test if this function is available at compile time check if the following macro is defined:

 #define LIBNBD_HAVE_NBD_SET_FULL_INFO 1

SEE ALSO

nbd_create(3), nbd_get_canonical_export_name(3), nbd_get_export_description(3), nbd_get_full_info(3), nbd_set_request_block_size(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