1.\" Copyright (c) 2002-2004 Tim J. Robbins 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23.\" SUCH DAMAGE. 24.\" 25.\" $FreeBSD: head/lib/libc/locale/wcrtomb.3 250883 2013-05-21 19:59:37Z ed $ 26.\" 27.Dd December 26, 2013 28.Dt WCRTOMB 3 29.Os 30.Sh NAME 31.Nm wcrtomb , 32.Nm wcrtomb_l , 33.Nm c16rtomb , 34.Nm c32rtomb 35.Nd "convert a wide-character code to a character (restartable)" 36.Sh LIBRARY 37.Lb libc 38.Sh SYNOPSIS 39.In wchar.h 40.Ft size_t 41.Fn wcrtomb "char * restrict s" "wchar_t c" "mbstate_t * restrict ps" 42.In uchar.h 43.Ft size_t 44.Fn c16rtomb "char * restrict s" "char16_t c" "mbstate_t * restrict ps" 45.Ft size_t 46.Fn c32rtomb "char * restrict s" "char32_t c" "mbstate_t * restrict ps" 47.In xlocale.h 48.Ft size_t 49.Fn wcrtomb_l "char * restrict s" "wchar_t c" "mbstate_t * restrict ps" "locale_t locale" 50.Sh DESCRIPTION 51The 52.Fn wcrtomb , 53.Fn wcrtomb_l , 54.Fn c16rtomb 55and 56.Fn c32rtomb 57functions store a multibyte sequence representing the 58wide character 59.Fa c , 60including any necessary shift sequences, to the 61character array 62.Fa s , 63storing a maximum of 64.Dv MB_CUR_MAX 65bytes. 66.Pp 67If 68.Fa s 69is 70.Dv NULL , 71these functions behave as if 72.Fa s 73pointed to an internal buffer and 74.Fa c 75was a null wide character (L'\e0'). 76.Pp 77The 78.Ft mbstate_t 79argument, 80.Fa ps , 81is used to keep track of the shift state. 82If it is 83.Dv NULL , 84these functions use an internal, static 85.Vt mbstate_t 86object, which is initialized to the initial conversion state 87at program startup. 88.Pp 89As certain multibyte characters may only be represented by a series of 9016-bit characters, the 91.Fn c16rtomb 92may need to invoked multiple times before a multibyte sequence is 93returned. 94.Pp 95The 96.Fn wcrtomb_l 97function takes an explicit 98.Fa locale 99argument, whereas the 100.Fn wcrtomb 101function uses the current global or per-thread locale. 102.Sh RETURN VALUES 103These functions return the length (in bytes) of the multibyte sequence 104needed to represent 105.Fa c , 106or 107.Po Vt size_t Pc Ns \-1 108if 109.Fa c 110is not a valid wide character code. 111.Sh ERRORS 112The 113.Fn wcrtomb , 114.Fn wcrtomb_l , 115.Fn c16rtomb 116and 117.Fn c32rtomb 118functions will fail if: 119.Bl -tag -width Er 120.It Bq Er EILSEQ 121An invalid wide character code was specified. 122.It Bq Er EINVAL 123The conversion state is invalid. 124.El 125.Sh SEE ALSO 126.Xr mbrtowc 3 , 127.Xr multibyte 3 , 128.Xr setlocale 3 , 129.Xr wcrtombin 3 , 130.Xr wcrtoutf8 3 , 131.Xr wctomb 3 , 132.Xr xlocale 3 133.Sh STANDARDS 134The 135.Fn wcrtomb , 136.Fn c16rtomb 137and 138.Fn c32rtomb 139functions conform to 140.St -isoC-2011 . 141