1nbd_trim(3) LIBNBD nbd_trim(3)
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6 nbd_trim - send trim command to the NBD server
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9 #include <libnbd.h>
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11 int nbd_trim (struct nbd_handle *h, uint64_t count,
12 uint64_t offset, uint32_t flags);
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15 Issue a trim command to the NBD server, which if supported by the
16 server causes a hole to be punched in the backing store starting at
17 "offset" and ending at "offset" + "count" - 1. The call returns when
18 the command has been acknowledged by the server, or there is an error.
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20 The "flags" parameter may be 0 for no flags, or may contain
21 "LIBNBD_CMD_FLAG_FUA" meaning that the server should not return until
22 the data has been committed to permanent storage (if that is supported
23 - some servers cannot do this, see nbd_can_fua(3)).
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26 If the call is successful the function returns 0.
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29 On error "-1" 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 The handle must be connected and finished handshaking with the server,
36 otherwise this call will return an error.
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39 This function first appeared in libnbd 1.0.
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41 If you need to test if this function is available at compile time check
42 if the following macro is defined:
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44 #define LIBNBD_HAVE_NBD_TRIM 1
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47 nbd_aio_trim(3), nbd_can_fua(3), nbd_can_trim(3), nbd_create(3),
48 libnbd(3).
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51 Eric Blake
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53 Richard W.M. Jones
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56 Copyright (C) 2019 Red Hat Inc.
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59 This library is free software; you can redistribute it and/or modify it
60 under the terms of the GNU Lesser General Public License as published
61 by the Free Software Foundation; either version 2 of the License, or
62 (at your option) any later version.
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64 This library is distributed in the hope that it will be useful, but
65 WITHOUT ANY WARRANTY; without even the implied warranty of
66 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
67 Lesser General Public License for more details.
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69 You should have received a copy of the GNU Lesser General Public
70 License along with this library; if not, write to the Free Software
71 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
72 02110-1301 USA
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76libnbd-1.3.7 2020-04-23 nbd_trim(3)