locale/FreeBSD/tolower.3

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  32 .\"     @(#)tolower.3   8.1 (Berkeley) 6/4/93
  33 .\" $FreeBSD: src/lib/libc/locale/tolower.3,v 1.21 2009/09/04 07:44:58 des Exp $
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  35 .Dd July 17, 2005
  36 .Dt TOLOWER 3
  37 .Os
  38 .Sh NAME
  39 .Nm tolower ,
  40 .Nm tolower_l
  41 .Nd upper case to lower case letter conversion
  42 .Sh LIBRARY
  43 .Lb libc
  44 .Sh SYNOPSIS
  45 .In ctype.h
  46 .Ft int
  47 .Fo tolower
  48 .Fa "int c"
  49 .Fc
  50 .In ctype.h
  51 .In xlocale.h
  52 .Ft int
  53 .Fo tolower_l
  54 .Fa "int c"
  55 .Fa "locale_t loc"
  56 .Fc
  57 .Sh DESCRIPTION
  58 The
  59 .Fn tolower
  60 function converts an upper-case letter to the corresponding lower-case
  61 letter.
  62 The argument must be representable as an
  63 .Vt "unsigned char"
  64 or the value of
  65 .Dv EOF .
  66 .Pp
  67 Although the
  68 .Fn tolower
  69 function uses the current locale, the
  70 .Fn tolower_l
  71 function may be passed a locale directly. See
  72 .Xr xlocale 3
  73 for more information.
  74 .Sh RETURN VALUES
  75 If the argument is an upper-case letter, the
  76 .Fn tolower
  77 function returns the corresponding lower-case letter if there is
  78 one; otherwise, the argument is returned unchanged.
  79 .Sh COMPATIBILITY
  80 The
  81 .Bx 4.4
  82 extension of accepting arguments outside of the range of the
  83 .Vt "unsigned char"
  84 type in locales with large character sets is considered obsolete
  85 and may not be supported in future releases.
  86 The
  87 .Fn towlower
  88 function should be used instead.
  89 .Sh SEE ALSO
  90 .Xr ctype 3 ,
  91 .Xr islower 3 ,
  92 .Xr towlower 3 ,
  93 .Xr xlocale 3
  94 .Sh STANDARDS
  95 The
  96 .Fn tolower
  97 function conforms to
  98 .St -isoC .