.\"	$NetBSD: uchar.3,v 1.2.2.2 2024/10/14 17:20:21 martin Exp $
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.Dd August 15, 2024
.Dt UCHAR 3
.Os
.\"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
.Sh NAME
.Nm uchar
.Nd Unicode utilities
.\"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
.Sh SYNOPSIS
.In uchar.h
.\"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
.Sh DESCRIPTION
The
.In uchar.h
header file declares types and functions for manipulating Unicode code
units.
.\""""""""""""""""""""""""""""""""""""""
.Ss Types
.Bl -tag -width ".Vt char32_t"
.It Vt char8_t
(C23)
Unsigned integer type for UTF-8 code units.
.Pp
Same type as
.Vt unsigned char .
.It Vt char16_t
Unsigned integer type for UTF-16 code units.
.Pp
Same type as
.Vt uint_least16_t
from
.In stdint.h .
May represent both surrogate code points, i.e., code points in the
interval [0xd800,0xdfff], and Unicode scalar values in the Basic
Multilingual Plane, which are the 16-bit code points other than
surrogate code points.
.It Vt char32_t
Unsigned integer type for UTF-32 code units.
.Pp
Same type as
.Vt uint_least32_t
from
.In stdint.h .
Can represent all Unicode scalar values, not just those in the Basic
Multilingual Plane.
Intended to represent only Unicode scalar values, not surrogate code
points.
.It Vt mbstate_t
Opaque multibyte conversion state.
.Pp
Same type as in
.Vt stddef.h
and
.Vt wchar.h .
.It Vt size_t
Unsigned integer type to represent array sizes.
.Pp
Same type as in
.Vt stddef.h ,
.Vt stdint.h ,
and
.Vt sys/types.h .
.El
.\""""""""""""""""""""""""""""""""""""""
.Ss Functions
The
.In uchar.h
header file declares the functions
.Xr mbrtoc8 3 ,
.Xr c8rtomb 3 ,
.Xr mbrtoc16 3 ,
.Xr c16rtomb 3 ,
.Xr mbrtoc32 3 ,
and
.Xr c32rtomb 3
for conversion between multibyte sequences and UTF-8/UTF-16/UTF-32 code
units.
.\"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
.Sh SEE ALSO
.Xr c8rtomb 3 ,
.Xr c16rtomb 3 ,
.Xr c32rtomb 3 ,
.Xr mbrtoc8 3 ,
.Xr mbrtoc16 3 ,
.Xr mbrtoc32 3
.Rs
.%B The Unicode Standard
.%O Version 15.0 \(em Core Specification
.%Q The Unicode Consortium
.%D September 2022
.%U https://www.unicode.org/versions/Unicode15.0.0/UnicodeStandard-15.0.pdf
.Re
.Rs
.%A P. Hoffman
.%A F. Yergeau
.%T UTF-16, an encoding of ISO 10646
.%R RFC 2781
.%D February 2000
.%I Internet Engineering Task Force
.%U https://datatracker.ietf.org/doc/html/rfc2781
.Re
.Rs
.%A F. Yergeau
.%T UTF-8, a transformation format of ISO 10646
.%R RFC 3629
.%D November 2003
.%I Internet Engineering Task Force
.%U https://datatracker.ietf.org/doc/html/rfc3629
.Re
.\"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
.Sh STANDARDS
The
.In uchar.h
header file conforms to
.St -isoC-2011
.\" .St -isoC-2023
.\" .\" XXX PR misc/58600: man pages lack C17, C23, C++98, C++03, C++11, C++17, C++20, C++23 citation syntax
and
.St -p1003.1-2024 .
.\"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
.Sh HISTORY
The
.In uchar.h
header file first appeared in
.Nx 11.0 .