1nbd_get_protocol(3)                 LIBNBD                 nbd_get_protocol(3)
2
3
4

NAME

6       nbd_get_protocol - return the NBD protocol variant
7

SYNOPSIS

9        #include <libnbd.h>
10
11        const char * nbd_get_protocol (
12                       struct nbd_handle *h
13                     );
14

DESCRIPTION

16       Return the NBD protocol variant in use on the connection.  At the
17       moment this returns one of the strings "oldstyle", "newstyle" or
18       "newstyle-fixed".  Other strings might be returned in the future.  Most
19       modern NBD servers use "newstyle-fixed".
20
21       This call does not block, because it returns data that is saved in the
22       handle from the NBD protocol handshake.
23

RETURN VALUE

25       This call returns a statically allocated string, valid for the lifetime
26       of the process or until libnbd is unloaded by dlclose(3).  You must not
27       try to free the string.
28

ERRORS

30       On error "NULL" is returned.
31
32       Refer to "ERROR HANDLING" in libnbd(3) for how to get further details
33       of the error.
34
35       The following parameters must not be NULL: "h".  For more information
36       see "Non-NULL parameters" in libnbd(3).
37

HANDLE STATE

39       The handle must be negotiating, or connected with the server, or shut
40       down, otherwise this call will return an error.
41

VERSION

43       This function first appeared in libnbd 1.2.
44
45       If you need to test if this function is available at compile time check
46       if the following macro is defined:
47
48        #define LIBNBD_HAVE_NBD_GET_PROTOCOL 1
49

SEE ALSO

51       nbd_create(3), nbd_get_block_size(3), nbd_get_handshake_flags(3),
52       nbd_get_structured_replies_negotiated(3), nbd_get_tls_negotiated(3),
53       libnbd(3).
54

AUTHORS

56       Eric Blake
57
58       Richard W.M. Jones
59

61       Copyright Red Hat
62

LICENSE

64       This library is free software; you can redistribute it and/or modify it
65       under the terms of the GNU Lesser General Public License as published
66       by the Free Software Foundation; either version 2 of the License, or
67       (at your option) any later version.
68
69       This library is distributed in the hope that it will be useful, but
70       WITHOUT ANY WARRANTY; without even the implied warranty of
71       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
72       Lesser General Public License for more details.
73
74       You should have received a copy of the GNU Lesser General Public
75       License along with this library; if not, write to the Free Software
76       Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
77       02110-1301 USA
78
79
80
81libnbd-1.18.1                     2023-10-31               nbd_get_protocol(3)
Impressum