xref: /freebsd/share/man/man9/dnv.9 (revision 2008043f386721d58158e37e0d7e50df8095942d)
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26.Dd July 26, 2016
27.Dt DNV 9
28.Os
29.Sh NAME
30.Nm dnvlist_get ,
31.Nm dnvlist_take
32.Nd "API for getting name/value pairs. Nonexistent pairs do not raise an error."
33.Sh LIBRARY
34.Lb libnv
35.Sh SYNOPSIS
36.In sys/dnv.h
37.Ft bool
38.Fn dnvlist_get_bool "const nvlist_t *nvl" "const char *name" "bool defval"
39.Ft uint64_t
40.Fn dnvlist_get_number "const nvlist_t *nvl" "const char *name" "uint64_t defval"
41.Ft char *
42.Fn dnvlist_get_string "const nvlist_t *nvl" "const char *name" "const char *defval"
43.Ft nvlist_t *
44.Fn dnvlist_get_nvlist "const nvlist_t *nvl" "const char *name" "nvlist_t *defval"
45.Ft int
46.Fn dnvlist_get_descriptor "const nvlist_t *nvl" "const char *name" "int defval"
47.Ft void *
48.Fn dnvlist_get_binary "const nvlist_t *nvl" "const char *name" "size_t *sizep" "void *defval" "size_t defsize"
49.Ft bool
50.Fn dnvlist_take_bool "const nvlist_t *nvl" "const char *name" "bool defval"
51.Ft uint64_t
52.Fn dnvlist_take_number "const nvlist_t *nvl" "const char *name" "uint64_t defval"
53.Ft char *
54.Fn dnvlist_take_string "const nvlist_t *nvl" "const char *name" "const char *defval"
55.Ft nvlist_t *
56.Fn dnvlist_take_nvlist "const nvlist_t *nvl" "const char *name" "nvlist_t *defval"
57.Ft int
58.Fn dnvlist_take_descriptor "const nvlist_t *nvl" "const char *name" "int defval"
59.Ft void *
60.Fn dnvlist_take_binary "const nvlist_t *nvl" "const char *name" "size_t *sizep" "void *defval" "size_t defsize"
61.Sh DESCRIPTION
62The
63.Nm libnv
64library permits easy management of name/value pairs and can send and receive
65them over sockets.
66For more information, also see
67.Xr nv 9 .
68.Pp
69The
70.Nm dnvlist_get
71family of functions returns the value associated with the specified name.
72If an element of the specified name does not exist, the function returns the
73value provided in
74.Fa defval .
75Returned strings, nvlists, descriptors, binaries, or arrays must not be modified
76by the user.
77They still belong to the nvlist.
78If the nvlist is in an error state, attempts to use any of these functions will
79cause the program to abort.
80.Pp
81The
82.Nm dnvlist_take
83family of functions returns the value associated with the specified name and
84removes the element from the nvlist.
85If an element of the supplied name does not exist, the value provided in
86.Nm defval
87is returned.
88When the value is a string, binary, or array value, the caller is
89responsible for freeing returned memory with
90.Fn free 3 .
91When the value is an nvlist, the caller is responsible for destroying the
92returned nvlist with
93.Fn nvlist_destroy .
94When the value is a descriptor, the caller is responsible for closing the
95returned descriptor with
96.Fn close 2 .
97.Sh SEE ALSO
98.Xr close 2 ,
99.Xr free 3 ,
100.Xr nv 9
101.Sh HISTORY
102The
103.Nm dnv
104API appeared in
105.Fx 11.0 .
106.Sh AUTHORS
107.An -nosplit
108The
109.Nm dnv
110API was implemented by
111.An Pawel Jakub Dawidek Aq Mt pawel@dawidek.net
112under sponsorship from the FreeBSD Foundation.
113This manual page was written by
114.An Adam Starak Aq Mt starak.adam@gmail.com
115