1nbd_aio_flush(3) LIBNBD nbd_aio_flush(3)
2
3
4
6 nbd_aio_flush - send flush command to the NBD server
7
9 #include <libnbd.h>
10
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;
16
17 int64_t nbd_aio_flush (struct nbd_handle *h,
18 nbd_completion_callback completion_callback,
19 uint32_t flags);
20
22 Issue the flush command to the NBD server.
23
24 To check if the command completed, call nbd_aio_command_completed(3).
25 Or supply the optional "completion_callback" which will be invoked as
26 described in "Completion callbacks" in libnbd(3).
27
28 Other parameters behave as documented in nbd_flush(3).
29
30 By default, libnbd will reject attempts to use this function with
31 parameters that are likely to result in server failure, such as
32 requesting an unknown command flag. The nbd_set_strict_mode(3)
33 function can be used to alter which scenarios should await a server
34 reply rather than failing fast.
35
37 This call returns the 64 bit cookie of the command. The cookie is ≥ 1.
38 Cookies are unique (per libnbd handle, not globally).
39
41 On error "-1" is returned.
42
43 Refer to "ERROR HANDLING" in libnbd(3) for how to get further details
44 of the error.
45
47 The handle must be connected with the server, otherwise this call will
48 return an error.
49
51 This function first appeared in libnbd 1.0.
52
53 If you need to test if this function is available at compile time check
54 if the following macro is defined:
55
56 #define LIBNBD_HAVE_NBD_AIO_FLUSH 1
57
59 nbd_aio_command_completed(3), nbd_can_flush(3), nbd_create(3),
60 nbd_flush(3), nbd_set_strict_mode(3), "Issuing asynchronous commands"
61 in libnbd(3), libnbd(3).
62
64 Eric Blake
65
66 Richard W.M. Jones
67
69 Copyright (C) 2019-2021 Red Hat Inc.
70
72 This library is free software; you can redistribute it and/or modify it
73 under the terms of the GNU Lesser General Public License as published
74 by the Free Software Foundation; either version 2 of the License, or
75 (at your option) any later version.
76
77 This library is distributed in the hope that it will be useful, but
78 WITHOUT ANY WARRANTY; without even the implied warranty of
79 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
80 Lesser General Public License for more details.
81
82 You should have received a copy of the GNU Lesser General Public
83 License along with this library; if not, write to the Free Software
84 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
85 02110-1301 USA
86
87
88
89libnbd-1.12.5 2022-07-10 nbd_aio_flush(3)