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.\" From FreeBSD: src/lib/libc/locale/multibyte.3,v 1.22 2003/11/08 03:23:11 tjr Exp 32.\" 33.Dd April 11, 2004 34.Dt MBLEN 3 35.Os 36.Sh NAME 37.Nm mblen 38.Nd get number of bytes in a character 39.Sh LIBRARY 40.Lb libc 41.Sh SYNOPSIS 42.In stdlib.h 43.Ft int 44.Fn mblen "const char *mbchar" "size_t nbytes" 45.Sh DESCRIPTION 46The 47.Fn mblen 48function computes the length in bytes 49of a multibyte character 50.Fa mbchar 51according to the current conversion state. 52Up to 53.Fa nbytes 54bytes are examined. 55.Pp 56A call with a null 57.Fa mbchar 58pointer returns nonzero if the current locale requires shift states, 59zero otherwise; 60if shift states are required, the shift state is reset to the initial state. 61.Sh RETURN VALUES 62If 63.Fa mbchar 64is 65.Dv NULL , 66the 67.Fn mblen 68function returns nonzero if shift states are supported, 69zero otherwise. 70.Pp 71Otherwise, if 72.Fa mbchar 73is not a null pointer, 74.Fn mblen 75either returns 0 if 76.Fa mbchar 77represents the null wide character, or returns 78the number of bytes processed in 79.Fa mbchar , 80or returns \-1 if no multibyte character 81could be recognized or converted. 82In this case, 83.Fn mblen Ns 's 84internal conversion state is undefined. 85.Sh ERRORS 86The 87.Fn mblen 88function will fail if: 89.Bl -tag -width Er 90.It Bq Er EILSEQ 91An invalid multibyte sequence was detected. 92.It Bq Er EINVAL 93The internal conversion state is not valid. 94.El 95.Sh SEE ALSO 96.Xr mbrlen 3 , 97.Xr mbtowc 3 , 98.Xr multibyte 3 99.Sh STANDARDS 100The 101.Fn mblen 102function conforms to 103.St -isoC-99 . 104