1nbd_flush(3) LIBNBD nbd_flush(3)
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6 nbd_flush - send flush command to the NBD server
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9 #include <libnbd.h>
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11 int nbd_flush (struct nbd_handle *h, uint32_t flags);
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14 Issue the flush command to the NBD server. The function should return
15 when all write commands which have completed have been committed to
16 permanent storage on the server. Note this will generally return an
17 error if nbd_can_flush(3) is false.
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19 The "flags" parameter must be 0 for now (it exists for future NBD
20 protocol extensions).
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22 By default, libnbd will reject attempts to use this function with
23 parameters that are likely to result in server failure, such as
24 requesting an unknown command flag. The nbd_set_strict_mode(3)
25 function can be used to alter which scenarios should await a server
26 reply rather than failing fast.
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29 If the call is successful the function returns 0.
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32 On error "-1" is returned.
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34 Refer to "ERROR HANDLING" in libnbd(3) for how to get further details
35 of the error.
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37 The following parameters must not be NULL: "h". For more information
38 see "Non-NULL parameters" in libnbd(3).
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41 The handle must be connected with the server, otherwise this call will
42 return an error.
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45 This function first appeared in libnbd 1.0.
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47 If you need to test if this function is available at compile time check
48 if the following macro is defined:
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50 #define LIBNBD_HAVE_NBD_FLUSH 1
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53 nbd_aio_flush(3), nbd_can_flush(3), nbd_create(3),
54 nbd_set_strict_mode(3), libnbd(3).
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57 Eric Blake
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59 Richard W.M. Jones
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62 Copyright (C) 2019-2021 Red Hat Inc.
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65 This library is free software; you can redistribute it and/or modify it
66 under the terms of the GNU Lesser General Public License as published
67 by the Free Software Foundation; either version 2 of the License, or
68 (at your option) any later version.
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70 This library is distributed in the hope that it will be useful, but
71 WITHOUT ANY WARRANTY; without even the implied warranty of
72 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
73 Lesser General Public License for more details.
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75 You should have received a copy of the GNU Lesser General Public
76 License along with this library; if not, write to the Free Software
77 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
78 02110-1301 USA
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82libnbd-1.14.2 2023-01-03 nbd_flush(3)