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