.\"	$NetBSD: prop_string.3,v 1.7 2009/12/14 06:06:22 dholland Exp $
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.\" by Jason R. Thorpe.
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.Dd January 21, 2008
.Dt PROP_STRING 3
.Os
.Sh NAME
.Nm prop_string ,
.Nm prop_string_create ,
.Nm prop_string_create_cstring ,
.Nm prop_string_create_cstring_nocopy ,
.Nm prop_string_copy ,
.Nm prop_string_copy_mutable ,
.Nm prop_string_size ,
.Nm prop_string_mutable ,
.Nm prop_string_cstring ,
.Nm prop_string_cstring_nocopy ,
.Nm prop_string_append ,
.Nm prop_string_append_cstring ,
.Nm prop_string_equals ,
.Nm prop_string_equals_cstring
.Nd string value property object
.Sh LIBRARY
.Lb libprop
.Sh SYNOPSIS
.In libprop/proplib.h
.\"
.Ft prop_string_t
.Fn prop_string_create "void"
.Ft prop_string_t
.Fn prop_string_create_cstring "const char *cstring"
.Ft prop_string_t
.Fn prop_string_create_cstring_nocopy "const char *cstring"
.\"
.Ft prop_string_t
.Fn prop_string_copy "prop_string_t string"
.Ft prop_string_t
.Fn prop_string_copy_mutable "prop_string_t string"
.\"
.Ft size_t
.Fn prop_string_size "prop_string_t string"
.Ft bool
.Fn prop_string_mutable "prop_string_t string"
.\"
.Ft char *
.Fn prop_string_cstring "prop_string_t string"
.Ft const char *
.Fn prop_string_cstring_nocopy "prop_string_t string"
.\"
.Ft bool
.Fn prop_string_append "prop_string_t str1" "prop_string_t str2"
.Ft bool
.Fn prop_string_append_cstring "prop_string_t string" "const char *cstring"
.\"
.Ft bool
.Fn prop_string_equals "prop_string_t str1" "prop_string_t str2"
.Ft bool
.Fn prop_string_equals_cstring "prop_string_t string" "const char *cstring"
.Sh DESCRIPTION
The
.Nm prop_string
family of functions operate on a string value property object type.
.Bl -tag -width "xxxxx"
.It Fn prop_string_create "void"
Create an empty mutable string.
Returns
.Dv NULL
on failure.
.It Fn prop_string_create_cstring "const char *cstring"
Create a mutable string that contains a copy of
.Fa cstring .
Returns
.Dv NULL
on failure.
.It Fn prop_string_create_cstring_nocopy "const char *cstring"
Create an immutable string that contains a reference to
.Fa cstring .
Returns
.Dv NULL
on failure.
.It Fn prop_string_copy "prop_string_t string"
Copy a string.
If the string being copied is an immutable external C string reference,
then the copy is also immutable and references the same external C string.
Returns
.Dv NULL
on failure.
.It Fn prop_string_copy_mutable "prop_string_t string"
Copy a string, always creating a mutable copy.
Returns
.Dv NULL
on failure.
.It Fn prop_string_size "prop_string_t string"
Returns the size of the string, not including the terminating NUL.
If the supplied object isn't a string, zero is returned.
.It Fn prop_string_mutable "prop_string_t string"
Returns
.Dv true
if the string is mutable.
If the supplied object isn't a string,
.Dv false
is returned.
.It Fn prop_string_cstring "prop_string_t string"
Returns a copy of the string's contents as a C string.
The caller is responsible for freeing the returned buffer.
.Pp
In user space, the buffer is allocated using
.Xr malloc 3 .
In the kernel, the buffer is allocated using
.Xr kmalloc 9
using the malloc type
.Dv M_TEMP .
.Pp
Returns
.Dv NULL
on failure.
.It Fn prop_string_cstring_nocopy "prop_string_t string"
Returns an immutable reference to the contents of the string as a
C string.
If the supplied object isn't a string,
.Dv NULL
is returned.
.It Fn prop_string_append "prop_string_t str1" "prop_string_t str2"
Append the contents of
.Fa str2
to
.Fa str1 ,
which must be mutable.
Returns
.Dv true
upon success and
.Dv false
otherwise.
.It Fn prop_string_append_cstring "prop_string_t string" "const char *cstring"
Append the C string
.Fa cstring
to
.Fa string ,
which must be mutable.
Returns
.Dv true
upon success and
.Dv false
otherwise.
.It Fn prop_string_equals "prop_string_t str1" "prop_string_t str2"
Returns
.Dv true
if the two string objects are equivalent.
.It Fn prop_string_equals_cstring "prop_string_t string" "const char *cstring"
Returns
.Dv true
if the string's value is equivalent to
.Fa cstring .
.El
.Sh SEE ALSO
.Xr prop_array 3 ,
.Xr prop_bool 3 ,
.Xr prop_data 3 ,
.Xr prop_dictionary 3 ,
.Xr prop_number 3 ,
.Xr prop_object 3 ,
.Xr proplib 3
.Sh HISTORY
The
.Nm proplib
property container object library first appeared in
.Nx 4.0 .