1.\" $OpenBSD: wcstombs.3,v 1.3 2007/05/31 19:19:29 jmc Exp $ 2.\" $NetBSD: wcstombs.3,v 1.5 2003/09/08 17:54:32 wiz Exp $ 3.\" 4.\" Copyright (c)2002 Citrus Project, 5.\" All rights reserved. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.Dd $Mdocdate: May 31 2007 $ 29.Dt WCSTOMBS 3 30.Os 31.\" ---------------------------------------------------------------------- 32.Sh NAME 33.Nm wcstombs 34.Nd converts a wide character string to a multibyte character string 35.\" ---------------------------------------------------------------------- 36.Sh SYNOPSIS 37.Fd #include <stdlib.h> 38.Ft size_t 39.Fn wcstombs "char * restrict s" "const wchar_t * restrict pwcs" "size_t n" 40.\" ---------------------------------------------------------------------- 41.Sh DESCRIPTION 42.Fn wcstombs 43converts the null-terminated wide character string pointed to by 44.Fa pwcs 45to the corresponding multibyte character string, 46and stores it in the array pointed to by 47.Fa s . 48This function may modify the first at most 49.Fa n 50bytes of the array pointed to by 51.Fa s . 52Each character will be converted as if 53.Xr wctomb 3 54is continuously called, except the internal state of 55.Xr wctomb 3 56will not be affected. 57.Pp 58For state-dependent encoding, the 59.Fn wcstombs 60implies the result multibyte character string pointed to by 61.Fa s 62always to begin with an initial state. 63.Pp 64The behaviour of the 65.Fn wcstombs 66is affected by the 67.Dv LC_CTYPE 68category of the current locale. 69.Pp 70There are special cases: 71.Bl -tag -width 012345678901 72.It s == NULL 73The 74.Fn wcstombs 75returns the number of bytes to store the whole multibyte character string 76corresponding to the wide character string pointed to by 77.Fa pwcs . 78In this case, 79.Fa n 80is ignored. 81.It pwcs == NULL 82Undefined (may causes the program to crash). 83.El 84.\" ---------------------------------------------------------------------- 85.Sh RETURN VALUES 86.Fn wcstombs 87returns: 88.Bl -tag -width 012345678901 89.It 0 or positive 90Number of bytes stored in the array pointed to by 91.Fa s . 92There are no cases that the value returned is greater than 93.Fa n 94(unless 95.Fa s 96is a null pointer). 97If the return value is equal to 98.Fa n , 99the string pointed to by 100.Fa s 101will not be null-terminated. 102.It (size_t)-1 103.Fa pwcs 104points the string containing invalid wide character. 105.Fn wcstombs 106also sets 107.Va errno 108to indicate the error. 109.El 110.\" ---------------------------------------------------------------------- 111.Sh ERRORS 112.Fn wcstombs 113may cause an error in the following cases: 114.Bl -tag -width Er 115.It Bq Er EILSEQ 116.Fa pwcs 117Points to the string containing invalid wide character. 118.El 119.\" ---------------------------------------------------------------------- 120.Sh SEE ALSO 121.Xr setlocale 3 , 122.Xr wctomb 3 123.\" ---------------------------------------------------------------------- 124.Sh STANDARDS 125The 126.Fn wcstombs 127function conforms to 128.St -ansiC . 129The restrict qualifier is added at 130.\" .St -isoC99 . 131ISO/IEC 9899/1999 132.Pq Dq ISO C99 . 133