nbd_get_meta_context(3)             LIBNBD             nbd_get_meta_context(3)


NAME
       nbd_get_meta_context - return the i'th meta context request

SYNOPSIS
        #include <libnbd.h>

        char * nbd_get_meta_context (
                 struct nbd_handle *h, size_t i
               );

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 returns the i'th meta context request, as added by
       nbd_add_meta_context(3), and bounded by nbd_get_nr_meta_contexts(3).

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).

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_GET_META_CONTEXT 1

SEE ALSO
       nbd_add_meta_context(3), nbd_block_status_64(3),
       nbd_can_meta_context(3), nbd_clear_meta_contexts(3), nbd_create(3),
       nbd_get_nr_meta_contexts(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_get_meta_context(3)