man3/wcswidth.3

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  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 .TH WCSWIDTH 3  2015-08-08 "GNU" "Linux Programmer's Manual"
  16 .SH NAME
  17 wcswidth \- determine columns needed for a fixed-size wide-character string
  18 .SH SYNOPSIS
  19 .nf
  20 .BR "#define _XOPEN_SOURCE" "             /* See feature_test_macros(7) */"
  21 .B #include <wchar.h>
  22 .PP
  23 .BI "int wcswidth(const wchar_t *" s ", size_t " n );
  24 .fi
  25 .SH DESCRIPTION
  26 The
  27 .BR wcswidth ()
  28 function returns the
  29 number of columns needed to represent
  30 the wide-character string pointed to by
  31 .IR s ,
  32 but at most
  33 .I n
  34 wide
  35 characters.
  36 If a nonprintable wide character occurs among these characters,
  37 \-1 is returned.
  38 .SH RETURN VALUE
  39 The
  40 .BR wcswidth ()
  41 function
  42 returns the number of column positions for the
  43 wide-character string
  44 .IR s ,
  45 truncated to at most length
  46 .IR n .
  47 .SH ATTRIBUTES
  48 For an explanation of the terms used in this section, see
  49 .BR attributes (7).
  50 .TS
  51 allbox;
  52 lb lb lb
  53 l l l.
  54 Interface       Attribute       Value
  55 T{
  56 .BR wcswidth ()
  57 T}      Thread safety   MT-Safe locale
  58 .TE
  59 .SH CONFORMING TO
  60 POSIX.1-2001, POSIX.1-2008.
  61 .SH NOTES
  62 The behavior of
  63 .BR wcswidth ()
  64 depends on the
  65 .B LC_CTYPE
  66 category of the
  67 current locale.
  68 .SH SEE ALSO
  69 .BR iswprint (3),
  70 .BR wcwidth (3)