1nbd_aio_trim(3) LIBNBD nbd_aio_trim(3)
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6 nbd_aio_trim - send trim 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, int *error);
13 void *user_data;
14 void (*free) (void *user_data);
15 } nbd_completion_callback;
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17 int64_t nbd_aio_trim (struct nbd_handle *h, uint64_t count,
18 uint64_t offset,
19 nbd_completion_callback completion_callback,
20 uint32_t flags);
21
23 Issue a trim command to the NBD server.
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25 To check if the command completed, call nbd_aio_command_completed(3).
26 Or supply the optional "completion_callback" which will be invoked as
27 described in "Completion callbacks" in libnbd(3).
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29 Other parameters behave as documented in nbd_trim(3).
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31 By default, libnbd will reject attempts to use this function with
32 parameters that are likely to result in server failure, such as
33 requesting an unknown command flag. The nbd_set_strict_mode(3)
34 function can be used to alter which scenarios should await a server
35 reply rather than failing fast.
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38 This call returns the 64 bit cookie of the command. The cookie is ≥ 1.
39 Cookies are unique (per libnbd handle, not globally).
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42 On error "-1" is returned.
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44 Refer to "ERROR HANDLING" in libnbd(3) for how to get further details
45 of the error.
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47 The following parameters must not be NULL: "h". For more information
48 see "Non-NULL parameters" in libnbd(3).
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51 The handle must be connected with the server, otherwise this call will
52 return an error.
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55 This function first appeared in libnbd 1.0.
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57 If you need to test if this function is available at compile time check
58 if the following macro is defined:
59
60 #define LIBNBD_HAVE_NBD_AIO_TRIM 1
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63 nbd_aio_command_completed(3), nbd_can_trim(3), nbd_create(3),
64 nbd_set_strict_mode(3), nbd_trim(3), "Issuing asynchronous commands" in
65 libnbd(3), libnbd(3).
66
68 Eric Blake
69
70 Richard W.M. Jones
71
73 Copyright (C) 2019-2021 Red Hat Inc.
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76 This library is free software; you can redistribute it and/or modify it
77 under the terms of the GNU Lesser General Public License as published
78 by the Free Software Foundation; either version 2 of the License, or
79 (at your option) any later version.
80
81 This library is distributed in the hope that it will be useful, but
82 WITHOUT ANY WARRANTY; without even the implied warranty of
83 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
84 Lesser General Public License for more details.
85
86 You should have received a copy of the GNU Lesser General Public
87 License along with this library; if not, write to the Free Software
88 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
89 02110-1301 USA
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93libnbd-1.14.2 2023-01-03 nbd_aio_trim(3)