f14fb60209
* Updating common/lib * Updating lib/csu * Updating lib/libc * Updating libexec/ld.elf_so * Corrected test on __minix in featuretest to actually follow the meaning of the comment. * Cleaned up _REENTRANT-related defintions. * Disabled -D_REENTRANT for libfetch * Removing some unneeded __NBSD_LIBC defines and tests Change-Id: Ic1394baef74d11b9f86b312f5ff4bbc3cbf72ce2
139 lines
4.4 KiB
Groff
139 lines
4.4 KiB
Groff
.\" $NetBSD: proplib.3,v 1.8 2012/03/15 22:35:02 njoly Exp $
|
|
.\"
|
|
.\" Copyright (c) 2006 The NetBSD Foundation, Inc.
|
|
.\" All rights reserved.
|
|
.\"
|
|
.\" This code is derived from software contributed to The NetBSD Foundation
|
|
.\" by Jason R. Thorpe.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
|
|
.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
|
|
.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
|
|
.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
|
|
.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
|
.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
|
.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
|
.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
|
.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
|
.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
.\" POSSIBILITY OF SUCH DAMAGE.
|
|
.\"
|
|
.Dd January 17, 2011
|
|
.Dt PROPLIB 3
|
|
.Os
|
|
.Sh NAME
|
|
.Nm proplib
|
|
.Nd property container object library
|
|
.Sh LIBRARY
|
|
.Lb libprop
|
|
.Sh SYNOPSIS
|
|
.In prop/proplib.h
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Nm
|
|
library provides an abstract interface for creating and manipulating
|
|
property lists.
|
|
Property lists have object types for boolean values, opaque data, numbers,
|
|
and strings.
|
|
Structure is provided by the array and dictionary collection types.
|
|
.Pp
|
|
Property lists can be passed across protection boundaries by translating
|
|
them to an external representation.
|
|
This external representation is an XML document whose format is described
|
|
by the following DTD:
|
|
.Bd -literal -offset indent
|
|
.Lk http://www.apple.com/DTDs/PropertyList-1.0.dtd
|
|
.Ed
|
|
.Pp
|
|
Property container objects are reference counted.
|
|
When an object is created, its reference count is set to 1.
|
|
Any code that keeps a reference to an object, including the collection
|
|
types
|
|
.Pq arrays and dictionaries ,
|
|
must
|
|
.Dq retain
|
|
the object
|
|
.Pq increment its reference count .
|
|
When that reference is dropped, the object must be
|
|
.Dq released
|
|
.Pq reference count decremented .
|
|
When an object's reference count drops to 0, it is automatically freed.
|
|
.Pp
|
|
The rules for managing reference counts are very simple:
|
|
.Bl -bullet
|
|
.It
|
|
If you create an object and do not explicitly maintain a reference to it,
|
|
you must release it.
|
|
.It
|
|
If you get a reference to an object from other code and wish to maintain
|
|
a reference to it, you must retain the object.
|
|
You are responsible for
|
|
releasing the object once you drop that reference.
|
|
.It
|
|
You must never release an object unless you create it or retain it.
|
|
.El
|
|
.Pp
|
|
Object collections may be iterated by creating a special iterator object.
|
|
Iterator objects are special; they may not be retained, and they are
|
|
released using an iterator-specific release function.
|
|
.Sh SEE ALSO
|
|
.Xr prop_array 3 ,
|
|
.Xr prop_bool 3 ,
|
|
.Xr prop_data 3 ,
|
|
.Xr prop_dictionary 3 ,
|
|
.Xr prop_dictionary_util 3 ,
|
|
.Xr prop_number 3 ,
|
|
.Xr prop_object 3 ,
|
|
.Xr prop_send_ioctl 3 ,
|
|
.Xr prop_send_syscall 3 ,
|
|
.Xr prop_string 3
|
|
.Sh HISTORY
|
|
The
|
|
.Nm
|
|
property container object library first appeared in
|
|
.Nx 4.0 .
|
|
.Sh CAVEATS
|
|
.Nm
|
|
does not have a
|
|
.Sq date
|
|
object type, and thus will not parse
|
|
.Sq date
|
|
elements from an Apple XML property list.
|
|
.Pp
|
|
The
|
|
.Nm
|
|
.Sq number
|
|
object type differs from the Apple XML property list format in the following
|
|
ways:
|
|
.Bl -bullet
|
|
.It
|
|
The external representation is in base 16, not base 10.
|
|
.Nm
|
|
is able to parse base 8, base 10, and base 16
|
|
.Sq integer
|
|
elements.
|
|
.It
|
|
Internally, integers are always stored as unsigned numbers
|
|
.Pq uint64_t .
|
|
Therefore, the external representation will never be negative.
|
|
.It
|
|
Because floating point numbers are not supported,
|
|
.Sq real
|
|
elements from an Apple XML property list will not be parsed.
|
|
.El
|
|
.Pp
|
|
In order to facilitate use of
|
|
.Nm
|
|
in kernel, standalone, and user space environments, the
|
|
.Nm
|
|
parser is not a real XML parser.
|
|
It is hard-coded to parse only the property list external representation.
|