xref: /freebsd/lib/libc/locale/tolower.3 (revision 5b86168f54047e3c31030899945a37ca8bd5db40)

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.\"	@(#)tolower.3	8.1 (Berkeley) 6/4/93
.\" $FreeBSD$
.\"
.Dd July 17, 2005
.Dt TOLOWER 3
.Os
.Sh NAME
.Nm tolower
.Nd upper case to lower case letter conversion
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In ctype.h
.Ft int
.Fn tolower "int c"
.Sh DESCRIPTION
The
.Fn tolower
function converts an upper-case letter to the corresponding lower-case
letter.
The argument must be representable as an
.Vt unsigned char
or the value of
.Dv EOF .
.Sh RETURN VALUES
If the argument is an upper-case letter, the
.Fn tolower
function returns the corresponding lower-case letter if there is
one; otherwise the argument is returned unchanged.
.Sh COMPATIBILITY
The
.Bx 4.4
extension of accepting arguments outside of the range of the
.Vt "unsigned char"
type in locales with large character sets is considered obsolete
and may not be supported in future releases.
The
.Fn towlower
function should be used instead.
.Sh SEE ALSO
.Xr ctype 3 ,
.Xr islower 3 ,
.Xr towlower 3
.Sh STANDARDS
The
.Fn tolower
function conforms to
.St -isoC .