1nbd_aio_block_status(3) LIBNBD nbd_aio_block_status(3)
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6 nbd_aio_block_status - send block status command to the NBD server
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9 #include <libnbd.h>
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11 typedef struct {
12 int (*callback) (void *user_data,
13 const char *metacontext,
14 uint64_t offset, uint32_t *entries,
15 size_t nr_entries, int *error);
16 void *user_data;
17 void (*free) (void *user_data);
18 } nbd_extent_callback;
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20 typedef struct {
21 int (*callback) (void *user_data, int *error);
22 void *user_data;
23 void (*free) (void *user_data);
24 } nbd_completion_callback;
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26 int64_t nbd_aio_block_status (struct nbd_handle *h,
27 uint64_t count,
28 uint64_t offset,
29 nbd_extent_callback extent_callback,
30 nbd_completion_callback completion_callback,
31 uint32_t flags);
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34 Send the block status command to the NBD server.
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36 To check if the command completed, call nbd_aio_command_completed(3).
37 Or supply the optional "completion_callback" which will be invoked as
38 described in "Completion callbacks" in libnbd(3).
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40 Other parameters behave as documented in nbd_block_status(3).
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43 This call returns the 64 bit cookie of the command. The cookie is ≥ 1.
44 Cookies are unique (per libnbd handle, not globally).
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47 On error "-1" is returned.
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49 Refer to "ERROR HANDLING" in libnbd(3) for how to get further details
50 of the error.
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53 The handle must be connected and finished handshaking with the server,
54 otherwise this call will return an error.
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57 This function first appeared in libnbd 1.0.
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59 If you need to test if this function is available at compile time check
60 if the following macro is defined:
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62 #define LIBNBD_HAVE_NBD_AIO_BLOCK_STATUS 1
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65 "Issuing asynchronous commands" in libnbd(3), nbd_can_meta_context(3),
66 nbd_block_status(3), nbd_create(3), libnbd(3).
67
69 Eric Blake
70
71 Richard W.M. Jones
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74 Copyright (C) 2019 Red Hat Inc.
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77 This library is free software; you can redistribute it and/or modify it
78 under the terms of the GNU Lesser General Public License as published
79 by the Free Software Foundation; either version 2 of the License, or
80 (at your option) any later version.
81
82 This library is distributed in the hope that it will be useful, but
83 WITHOUT ANY WARRANTY; without even the implied warranty of
84 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
85 Lesser General Public License for more details.
86
87 You should have received a copy of the GNU Lesser General Public
88 License along with this library; if not, write to the Free Software
89 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
90 02110-1301 USA
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94libnbd-1.2.1 2019-11-14 nbd_aio_block_status(3)