man3/MB_LEN_MAX.3


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.\" Copyright (c) Bruno Haible <haible@clisp.cons.org>
.\"
.\" SPDX-License-Identifier: GPL-2.0-or-later
.\"
.\" References consulted:
.\"   GNU glibc-2 source code and manual
.\"   Dinkumware C library reference http://www.dinkumware.com/
.\"   OpenGroup's Single UNIX specification http://www.UNIX-systems.org/online.html
.\"
.\" Modified, aeb, 990824
.\"
.TH MB_LEN_MAX 3 (date) "Linux man-pages (unreleased)"
.SH NAME
MB_LEN_MAX \- maximum multibyte length of a character across all locales
.SH LIBRARY
Standard C library
.RI ( libc )
.SH SYNOPSIS
.nf
.B #include <limits.h>
.fi
.SH DESCRIPTION
The
.B MB_LEN_MAX
macro is the maximum number of bytes needed to represent a single
wide character, in any of the supported locales.
.SH RETURN VALUE
A constant integer greater than zero.
.SH STANDARDS
C11, POSIX.1-2008.
.SH HISTORY
C99, POSIX.1-2001.
.SH NOTES
The entities
.B MB_LEN_MAX
and
.I sizeof(wchar_t)
are totally unrelated.
In glibc,
.B MB_LEN_MAX
is typically 16
.\" For an explanation of why the limit was raised to 16, see
.\" http://lists.gnu.org/archive/html/bug-gnulib/2015-05/msg00001.html
.\"     From:    Bruno Haible
.\"     Subject: Re: why is MB_LEN_MAX so large (16) on glibc
.\"     Date:    Thu, 14 May 2015 02:30:14 +0200
(6 in glibc versions earlier than 2.2), while
.I sizeof(wchar_t)
is 4.
.SH SEE ALSO
.BR MB_CUR_MAX (3)