1nbd_aio_pwrite(3)                   LIBNBD                   nbd_aio_pwrite(3)
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NAME

6       nbd_aio_pwrite - write to the NBD server
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SYNOPSIS

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;
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17        int64_t nbd_aio_pwrite (struct nbd_handle *h,
18                                const void *buf, size_t count,
19                                uint64_t offset,
20                                nbd_completion_callback completion_callback,
21                                uint32_t flags);
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DESCRIPTION

24       Issue a write command to the NBD server.
25
26       To check if the command completed, call nbd_aio_command_completed(3).
27       Or supply the optional "completion_callback" which will be invoked as
28       described in "Completion callbacks" in libnbd(3).
29
30       Note that you must ensure "buf" is valid until the command has
31       completed.  Other parameters behave as documented in nbd_pwrite(3).
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RETURN VALUE

34       This call returns the 64 bit cookie of the command.  The cookie is ≥ 1.
35       Cookies are unique (per libnbd handle, not globally).
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ERRORS

38       On error "-1" is returned.
39
40       Refer to "ERROR HANDLING" in libnbd(3) for how to get further details
41       of the error.
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HANDLE STATE

44       The handle must be connected and finished handshaking with the server,
45       otherwise this call will return an error.
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VERSION

48       This function first appeared in libnbd 1.0.
49
50       If you need to test if this function is available at compile time check
51       if the following macro is defined:
52
53        #define LIBNBD_HAVE_NBD_AIO_PWRITE 1
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SEE ALSO

56       nbd_aio_command_completed(3), nbd_create(3), nbd_is_read_only(3),
57       nbd_pwrite(3), "Issuing asynchronous commands" in libnbd(3), libnbd(3).
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AUTHORS

60       Eric Blake
61
62       Richard W.M. Jones
63

65       Copyright (C) 2019 Red Hat Inc.
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LICENSE

68       This library is free software; you can redistribute it and/or modify it
69       under the terms of the GNU Lesser General Public License as published
70       by the Free Software Foundation; either version 2 of the License, or
71       (at your option) any later version.
72
73       This library is distributed in the hope that it will be useful, but
74       WITHOUT ANY WARRANTY; without even the implied warranty of
75       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
76       Lesser General Public License for more details.
77
78       You should have received a copy of the GNU Lesser General Public
79       License along with this library; if not, write to the Free Software
80       Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
81       02110-1301 USA
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85libnbd-1.3.7                      2020-04-23                 nbd_aio_pwrite(3)
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