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.\" $FreeBSD$ 26.\" 27.Dd May 21, 2013 28.Dt WCRTOMB 3 29.Os 30.Sh NAME 31.Nm wcrtomb , 32.Nm c16rtomb , 33.Nm c32rtomb 34.Nd "convert a wide-character code to a character (restartable)" 35.Sh LIBRARY 36.Lb libc 37.Sh SYNOPSIS 38.In wchar.h 39.Ft size_t 40.Fn wcrtomb "char * restrict s" "wchar_t c" "mbstate_t * restrict ps" 41.In uchar.h 42.Ft size_t 43.Fn c16rtomb "char * restrict s" "char16_t c" "mbstate_t * restrict ps" 44.Ft size_t 45.Fn c32rtomb "char * restrict s" "char32_t c" "mbstate_t * restrict ps" 46.Sh DESCRIPTION 47The 48.Fn wcrtomb , 49.Fn c16rtomb 50and 51.Fn c32rtomb 52functions store a multibyte sequence representing the 53wide character 54.Fa c , 55including any necessary shift sequences, to the 56character array 57.Fa s , 58storing a maximum of 59.Dv MB_CUR_MAX 60bytes. 61.Pp 62If 63.Fa s 64is 65.Dv NULL , 66these functions behave as if 67.Fa s 68pointed to an internal buffer and 69.Fa c 70was a null wide character (L'\e0'). 71.Pp 72The 73.Ft mbstate_t 74argument, 75.Fa ps , 76is used to keep track of the shift state. 77If it is 78.Dv NULL , 79these functions use an internal, static 80.Vt mbstate_t 81object, which is initialized to the initial conversion state 82at program startup. 83.Pp 84As certain multibyte characters may only be represented by a series of 8516-bit characters, the 86.Fn c16rtomb 87may need to invoked multiple times before a multibyte sequence is 88returned. 89.Sh RETURN VALUES 90These functions return the length (in bytes) of the multibyte sequence 91needed to represent 92.Fa c , 93or 94.Po Vt size_t Pc Ns \-1 95if 96.Fa c 97is not a valid wide character code. 98.Sh ERRORS 99The 100.Fn wcrtomb , 101.Fn c16rtomb 102and 103.Fn c32rtomb 104functions will fail if: 105.Bl -tag -width Er 106.It Bq Er EILSEQ 107An invalid wide character code was specified. 108.It Bq Er EINVAL 109The conversion state is invalid. 110.El 111.Sh SEE ALSO 112.Xr mbrtowc 3 , 113.Xr multibyte 3 , 114.Xr setlocale 3 , 115.Xr wctomb 3 116.Sh STANDARDS 117The 118.Fn wcrtomb , 119.Fn c16rtomb 120and 121.Fn c32rtomb 122functions conform to 123.St -isoC-2011 . 124