1.\" $NetBSD: wcstombs.3,v 1.3 2002/03/25 20:01:22 yamt Exp $ 2.\" 3.\" Copyright (c)2002 Citrus Project, 4.\" All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25.\" SUCH DAMAGE. 26.\" 27.Dd February 4, 2002 28.Dt WCSTOMBS 3 29.Os 30.\" ---------------------------------------------------------------------- 31.Sh NAME 32.Nm wcstombs 33.Nd converts a wide character string to a multibyte character string 34.\" ---------------------------------------------------------------------- 35.Sh LIBRARY 36.Lb libc 37.\" ---------------------------------------------------------------------- 38.Sh SYNOPSIS 39.Fd #include \*[Lt]stdlib.h\*[Gt] 40.Ft size_t 41.Fn wcstombs "const char * restrict s" "wchar_t * restrict pwcs" "size_t n" 42.\" ---------------------------------------------------------------------- 43.Sh DESCRIPTION 44The 45.Fn wcstombs 46converts the null-terminated wide character string pointed by 47.Fa pwcs 48to the corresponding multibyte character string, 49and store it to the array pointed by 50.Fa s . 51This function may modify the first at most 52.Fa n 53bytes of the array pointed by 54.Fa s . 55Each characters will be converted as if 56.Xr wctomb 3 57is continuously called, except the internal state of 58.Xr wctomb 3 59will not be affected. 60.Pp 61For state-dependent encoding, the 62.Fn wcstombs 63implies the result multibyte character string pointed by 64.Fa s 65always to begin with an initial state. 66.Pp 67The behaviour of the 68.Fn wcstombs 69is affected by LC_CTYPE category of the current locale. 70.Pp 71There are special cases: 72.Bl -tag -width 012345678901 73.It s == NULL 74The 75.Fn wcstombs 76returns the number of bytes to store the whole multibyte character string 77corresponding to the wide character string pointed by 78.Fa pwcs . 79In this case, 80.Fa n 81is ignored. 82.It pwcs == NULL 83undefined (may causes the program to crash). 84.El 85.\" ---------------------------------------------------------------------- 86.Sh RETURN VALUES 87The 88.Fn wcstombs 89returns: 90.Bl -tag -width 012345678901 91.It 0 or positive 92number of bytes stored to the array pointed by 93.Fa s . 94There is no cases that the value returned is greater than 95.Fa n 96(unless 97.Fa s 98is a null pointer). 99If the return value is equal to 100.Fa n , 101the string pointed by 102.Fa s 103will not be null-terminated. 104.It (size_t)-1 105.Fa pwcs 106points the string containing invalid wide character. 107The 108.Fn wcstombs 109also sets errno to indicate the error. 110.El 111.\" ---------------------------------------------------------------------- 112.Sh ERRORS 113The 114.Fn wcstombs 115may causes an error in the following case: 116.Bl -tag -width Er 117.It Bq Er EILSEQ 118.Fa pwcs 119points the string containing invalid wide character. 120.El 121.\" ---------------------------------------------------------------------- 122.Sh SEE ALSO 123.Xr setlocale 3 , 124.Xr wctomb 3 125.\" ---------------------------------------------------------------------- 126.Sh STANDARDS 127The 128.Fn wcstombs 129function conforms to 130.St -ansiC . 131The restrict qualifier is added at 132.St -isoC99 . 133