1.\" Copyright (c) 2002-2004 Tim J. Robbins. All rights reserved. 2.\" Copyright (c) 1993 3.\" The Regents of the University of California. All rights reserved. 4.\" 5.\" This code is derived from software contributed to Berkeley by 6.\" Donn Seeley of BSDI. 7.\" 8.\" Redistribution and use in source and binary forms, with or without 9.\" modification, are permitted provided that the following conditions 10.\" are met: 11.\" 1. Redistributions of source code must retain the above copyright 12.\" notice, this list of conditions and the following disclaimer. 13.\" 2. Redistributions in binary form must reproduce the above copyright 14.\" notice, this list of conditions and the following disclaimer in the 15.\" documentation and/or other materials provided with the distribution. 16.\" 3. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" From @(#)multibyte.3 8.1 (Berkeley) 6/4/93 33.\" From FreeBSD: src/lib/libc/locale/multibyte.3,v 1.22 2003/11/08 03:23:11 tjr Exp 34.\" $FreeBSD: head/lib/libc/locale/mbstowcs.3 165903 2007-01-09 00:28:16Z imp $ 35.\" 36.Dd December 26, 2013 37.Dt MBSTOWCS 3 38.Os 39.Sh NAME 40.Nm mbstowcs , 41.Nm mbstowcs_l 42.Nd convert a character string to a wide-character string 43.Sh LIBRARY 44.Lb libc 45.Sh SYNOPSIS 46.In stdlib.h 47.Ft size_t 48.Fo mbstowcs 49.Fa "wchar_t * restrict wcstring" "const char * restrict mbstring" 50.Fa "size_t nwchars" 51.Fc 52.In xlocale.h 53.Ft size_t 54.Fo mbstowcs_l 55.Fa "wchar_t * restrict wcstring" "const char * restrict mbstring" 56.Fa "size_t nwchars" "locale_t locale" 57.Fc 58.Sh DESCRIPTION 59The 60.Fn mbstowcs 61and 62.Fn mbstowcs_l 63functions convert a multibyte character string 64.Fa mbstring 65beginning in the initial conversion state 66into a wide character string 67.Fa wcstring . 68No more than 69.Fa nwchars 70wide characters are stored. 71A terminating null wide character is appended if there is room. 72.Pp 73The 74.Fn mbstowcs_l 75function takes an explicit 76.Fa locale 77argument, whereas the 78.Fn mbstowcs 79function uses the current global or per-thread locale. 80.Sh RETURN VALUES 81The 82.Fn mbstowcs 83and 84.Fn mbstowcs_l 85functions return the number of wide characters converted, 86not counting any terminating null wide character, or \-1 87if an invalid multibyte character was encountered. 88.Sh ERRORS 89The 90.Fn mbstowcs 91and 92.Fn mbstowcs_l 93functions will fail if: 94.Bl -tag -width Er 95.It Bq Er EILSEQ 96An invalid multibyte sequence was detected. 97.It Bq Er EINVAL 98The conversion state is invalid. 99.El 100.Sh SEE ALSO 101.Xr mbsrtowcs 3 , 102.Xr mbtowc 3 , 103.Xr multibyte 3 , 104.Xr xlocale 3 105.Sh STANDARDS 106The 107.Fn mbstowcs 108function conforms to 109.St -isoC-99 . 110