1.\" 2.\" Copyright (c) 2016 Adam Starak <starak.adam@gmail.com> 3.\" All rights reserved. 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions and the following disclaimer. 10.\" 2. Redistributions in binary form must reproduce the above copyright 11.\" notice, this list of conditions and the following disclaimer in the 12.\" documentation and/or other materials provided with the distribution. 13.\" 14.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24.\" SUCH DAMAGE. 25.\" 26.\" $FreeBSD$ 27.\" 28.Dd July 26, 2016 29.Dt DNV 9 30.Os 31.Sh NAME 32.Nm dnvlist_get , 33.Nm dnvlist_take 34.Nd "API for getting name/value pairs. Nonexistent pairs do not raise an error." 35.Sh LIBRARY 36.Lb libnv 37.Sh SYNOPSIS 38.In sys/dnv.h 39.Ft bool 40.Fn dnvlist_get_bool "const nvlist_t *nvl" "const char *name" "bool defval" 41.Ft uint64_t 42.Fn dnvlist_get_number "const nvlist_t *nvl" "const char *name" "uint64_t defval" 43.Ft char * 44.Fn dnvlist_get_string "const nvlist_t *nvl" "const char *name" "const char *defval" 45.Ft nvlist_t * 46.Fn dnvlist_get_nvlist "const nvlist_t *nvl" "const char *name" "nvlist_t *defval" 47.Ft int 48.Fn dnvlist_get_descriptor "const nvlist_t *nvl" "const char *name" "int defval" 49.Ft void * 50.Fn dnvlist_get_binary "const nvlist_t *nvl" "const char *name" "size_t *sizep" "void *defval" "size_t defsize" 51.Ft bool 52.Fn dnvlist_take_bool "const nvlist_t *nvl" "const char *name" "bool defval" 53.Ft uint64_t 54.Fn dnvlist_take_number "const nvlist_t *nvl" "const char *name" "uint64_t defval" 55.Ft char * 56.Fn dnvlist_take_string "const nvlist_t *nvl" "const char *name" "const char *defval" 57.Ft nvlist_t * 58.Fn dnvlist_take_nvlist "const nvlist_t *nvl" "const char *name" "nvlist_t *defval" 59.Ft int 60.Fn dnvlist_take_descriptor "const nvlist_t *nvl" "const char *name" "int defval" 61.Ft void * 62.Fn dnvlist_take_binary "const nvlist_t *nvl" "const char *name" "size_t *sizep" "void *defval" "size_t defsize" 63.Sh DESCRIPTION 64The 65.Nm libnv 66library permits easy management of name/value pairs and can send and receive 67them over sockets. 68For more information, also see 69.Xr nv 9 . 70.Pp 71The 72.Nm dnvlist_get 73family of functions returns the value associated with the specified name. 74If an element of the specified name does not exist, the function returns the 75value provided in 76.Fa defval . 77Returned strings, nvlists, descriptors, binaries, or arrays must not be modified 78by the user. 79They still belong to the nvlist. 80If the nvlist is in an error state, attempts to use any of these functions will 81cause the program to abort. 82.Pp 83The 84.Nm dnvlist_take 85family of functions returns the value associated with the specified name and 86removes the element from the nvlist. 87If an element of the supplied name does not exist, the value provided in 88.Nm defval 89is returned. 90When the value is a string, binary, or array value, the caller is 91responsible for freeing returned memory with 92.Fn free 3 . 93When the value is an nvlist, the caller is responsible for destroying the 94returned nvlist with 95.Fn nvlist_destroy . 96When the value is a descriptor, the caller is responsible for closing the 97returned descriptor with 98.Fn close 2 . 99.Sh SEE ALSO 100.Xr close 2 , 101.Xr free 3 , 102.Xr nv 9 103.Sh HISTORY 104The 105.Nm dnv 106API appeared in 107.Fx 11.0 . 108.Sh AUTHORS 109.An -nosplit 110The 111.Nm dnv 112API was implemented by 113.An Pawel Jakub Dawidek Aq Mt pawel@dawidek.net 114under sponsorship from the FreeBSD Foundation. 115This manual page was written by 116.An Adam Starak Aq Mt starak.adam@gmail.com 117