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.\" 4. 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/mblen.3 165903 2007-01-09 00:28:16Z imp $ 35.\" 36.Dd April 11, 2004 37.Dt MBLEN 3 38.Os 39.Sh NAME 40.Nm mblen 41.Nd get number of bytes in a character 42.Sh LIBRARY 43.Lb libc 44.Sh SYNOPSIS 45.In stdlib.h 46.Ft int 47.Fn mblen "const char *mbchar" "size_t nbytes" 48.Sh DESCRIPTION 49The 50.Fn mblen 51function computes the length in bytes 52of a multibyte character 53.Fa mbchar 54according to the current conversion state. 55Up to 56.Fa nbytes 57bytes are examined. 58.Pp 59A call with a null 60.Fa mbchar 61pointer returns nonzero if the current locale requires shift states, 62zero otherwise; 63if shift states are required, the shift state is reset to the initial state. 64.Sh RETURN VALUES 65If 66.Fa mbchar 67is 68.Dv NULL , 69the 70.Fn mblen 71function returns nonzero if shift states are supported, 72zero otherwise. 73.Pp 74Otherwise, if 75.Fa mbchar 76is not a null pointer, 77.Fn mblen 78either returns 0 if 79.Fa mbchar 80represents the null wide character, or returns 81the number of bytes processed in 82.Fa mbchar , 83or returns \-1 if no multibyte character 84could be recognized or converted. 85In this case, 86.Fn mblen Ns 's 87internal conversion state is undefined. 88.Sh ERRORS 89The 90.Fn mblen 91function will fail if: 92.Bl -tag -width Er 93.It Bq Er EILSEQ 94An invalid multibyte sequence was detected. 95.It Bq Er EINVAL 96The internal conversion state is not valid. 97.El 98.Sh SEE ALSO 99.Xr mbrlen 3 , 100.Xr mbtowc 3 , 101.Xr multibyte 3 102.Sh STANDARDS 103The 104.Fn mblen 105function conforms to 106.St -isoC-99 . 107