man3/MB_LEN_MAX.3

   1 .\" Copyright (c) Bruno Haible <haible@clisp.cons.org>
   2 .\"
   3 .\" SPDX-License-Identifier: GPL-2.0-or-later
   4 .\"
   5 .\" References consulted:
   6 .\"   GNU glibc-2 source code and manual
   7 .\"   Dinkumware C library reference http://www.dinkumware.com/
   8 .\"   OpenGroup's Single UNIX specification http://www.UNIX-systems.org/online.html
   9 .\"
  10 .\" Modified, aeb, 990824
  11 .\"
  12 .TH MB_LEN_MAX 3 2015-07-23 "Linux man-pages (unreleased)"
  13 .SH NAME
  14 MB_LEN_MAX \- maximum multibyte length of a character across all locales
  15 .SH LIBRARY
  16 Standard C library
  17 .RI ( libc )
  18 .SH SYNOPSIS
  19 .nf
  20 .B #include <limits.h>
  21 .fi
  22 .SH DESCRIPTION
  23 The
  24 .B MB_LEN_MAX
  25 macro is the maximum number of bytes needed to represent a single
  26 wide character, in any of the supported locales.
  27 .SH RETURN VALUE
  28 A constant integer greater than zero.
  29 .SH STANDARDS
  30 POSIX.1-2001, POSIX.1-2008, C99.
  31 .SH NOTES
  32 The entities
  33 .B MB_LEN_MAX
  34 and
  35 .I sizeof(wchar_t)
  36 are totally unrelated.
  37 In glibc,
  38 .B MB_LEN_MAX
  39 is typically 16
  40 .\" For an explanation of why the limit was raised to 16, see
  41 .\" http://lists.gnu.org/archive/html/bug-gnulib/2015-05/msg00001.html
  42 .\"     From:    Bruno Haible
  43 .\"     Subject: Re: why is MB_LEN_MAX so large (16) on glibc
  44 .\"     Date:    Thu, 14 May 2015 02:30:14 +0200
  45 (6 in glibc versions earlier than 2.2), while
  46 .I sizeof(wchar_t)
  47 is 4.
  48 .SH SEE ALSO
  49 .BR MB_CUR_MAX (3)