1nbd_get_meta_context(3) LIBNBD nbd_get_meta_context(3)
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6 nbd_get_meta_context - return the i'th meta context request
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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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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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25 This call returns a string. The caller must free the returned string
26 to avoid a memory leak.
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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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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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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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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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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.
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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.
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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-1.10.1 2021-10-25 nbd_get_meta_context(3)