1nbd_get_meta_context(3)             LIBNBD             nbd_get_meta_context(3)
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NAME

6       nbd_get_meta_context - return the i'th meta context request
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SYNOPSIS

9        #include <libnbd.h>
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11        char * nbd_get_meta_context (struct nbd_handle *h,
12                                     size_t i);
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DESCRIPTION

15       During connection libnbd can negotiate zero or more metadata contexts
16       with the server.  Metadata contexts are features (such as
17       "base:allocation") which describe information returned by the
18       nbd_block_status(3) command (for "base:allocation" this is whether
19       blocks of data are allocated, zero or sparse).
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21       This command returns the i'th meta context request, as added by
22       nbd_add_meta_context(3), and bounded by nbd_get_nr_meta_contexts(3).
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RETURN VALUE

25       This call returns a string.  The caller must free the returned string
26       to avoid a memory leak.
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ERRORS

29       On error "NULL" is returned.
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31       Refer to "ERROR HANDLING" in libnbd(3) for how to get further details
32       of the error.
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VERSION

35       This function first appeared in libnbd 1.6.
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37       If you need to test if this function is available at compile time check
38       if the following macro is defined:
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40        #define LIBNBD_HAVE_NBD_GET_META_CONTEXT 1
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SEE ALSO

43       nbd_add_meta_context(3), nbd_block_status(3), nbd_can_meta_context(3),
44       nbd_clear_meta_contexts(3), nbd_create(3), nbd_get_nr_meta_contexts(3),
45       libnbd(3).
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AUTHORS

48       Eric Blake
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50       Richard W.M. Jones
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53       Copyright (C) 2019-2021 Red Hat Inc.
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LICENSE

56       This library is free software; you can redistribute it and/or modify it
57       under the terms of the GNU Lesser General Public License as published
58       by the Free Software Foundation; either version 2 of the License, or
59       (at your option) any later version.
60
61       This library is distributed in the hope that it will be useful, but
62       WITHOUT ANY WARRANTY; without even the implied warranty of
63       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
64       Lesser General Public License for more details.
65
66       You should have received a copy of the GNU Lesser General Public
67       License along with this library; if not, write to the Free Software
68       Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
69       02110-1301 USA
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73libnbd-1.7.12                     2021-05-29           nbd_get_meta_context(3)
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