1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
|
=head1 NAME
nbd_get_meta_context - return the i'th meta context request
=head1 SYNOPSIS
#include <libnbd.h>
char * nbd_get_meta_context (
struct nbd_handle *h, size_t i
);
=head1 DESCRIPTION
During connection libnbd can negotiate zero or more metadata
contexts with the server. Metadata contexts are features (such
as C<"base:allocation">) which describe information returned
by the L<nbd_block_status_64(3)> command (for C<"base:allocation">
this is whether blocks of data are allocated, zero or sparse).
This command returns the i'th meta context request, as added by
L<nbd_add_meta_context(3)>, and bounded by
L<nbd_get_nr_meta_contexts(3)>.
=head1 RETURN VALUE
This call returns a string. The caller must free the
returned string to avoid a memory leak.
=head1 ERRORS
On error C<NULL> is returned.
Refer to L<libnbd(3)/ERROR HANDLING>
for how to get further details of the error.
The following parameters must not be NULL: C<h>.
For more information see L<libnbd(3)/Non-NULL parameters>.
=head1 VERSION
This function first appeared in libnbd 1.6.
If you need to test if this function is available at compile time
check if the following macro is defined:
#define LIBNBD_HAVE_NBD_GET_META_CONTEXT 1
=head1 SEE ALSO
L<nbd_add_meta_context(3)>,
L<nbd_block_status_64(3)>,
L<nbd_can_meta_context(3)>,
L<nbd_clear_meta_contexts(3)>,
L<nbd_create(3)>,
L<nbd_get_nr_meta_contexts(3)>,
L<libnbd(3)>.
=head1 AUTHORS
Eric Blake
Richard W.M. Jones
=head1 COPYRIGHT
Copyright Red Hat
|
