NAME

       nbd_clear_meta_contexts - reset the list of requested meta contexts

SYNOPSIS

        #include <libnbd.h>

        int nbd_clear_meta_contexts (
              struct nbd_handle *h
            );

DESCRIPTION

       During connection libnbd can negotiate zero or more metadata contexts with the server.
       Metadata contexts are features (such as "base:allocation") which describe information
       returned by the nbd_block_status_64(3) command (for "base:allocation" this is whether
       blocks of data are allocated, zero or sparse).

       This command resets the list of meta contexts to request back to an empty list, for re-
       population by further use of nbd_add_meta_context(3).  It is primarily useful when option
       negotiation mode is selected (see nbd_set_opt_mode(3)), for altering the list of attempted
       contexts between subsequent export queries.

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_clear_meta_contexts 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 1.6.

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

        #define LIBNBD_HAVE_NBD_CLEAR_META_CONTEXTS 1

SEE ALSO

       nbd_add_meta_context(3), nbd_block_status_64(3), nbd_can_meta_context(3), nbd_create(3),
       nbd_get_meta_context(3), nbd_get_nr_meta_contexts(3), nbd_set_opt_mode(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