man3/MB_LEN_MAX.3

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