xref: /freebsd/lib/libc/locale/tolower.3 (revision 25bb73e063c17cd9048cf60100dbc0ac5177e94a)

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.\"	@(#)tolower.3	8.1 (Berkeley) 6/4/93
.\" $FreeBSD$
.\"
.Dd June 4, 1993
.Dt TOLOWER 3
.Os
.Sh NAME
.Nm tolower
.Nd upper case to lower case letter conversion
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.Fd #include <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.
For 8-bit wide locales the value of the argument is
representable as an unsigned char or the value of 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.
.\" In the
.\" .Em ``C''
.\" locale,
.\" .Fn tolower
.\" maps only the characters for which
.\" .Xr isupper
.\" is true to the corresponding characters for which
.\" .Xr islower
.\" is true.
.Sh SEE ALSO
.Xr isalnum 3 ,
.Xr isalpha 3 ,
.Xr isascii 3 ,
.Xr iscntrl 3 ,
.Xr isdigit 3 ,
.Xr isgraph 3 ,
.Xr islower 3 ,
.Xr isprint 3 ,
.Xr ispunct 3 ,
.Xr isspace 3 ,
.Xr isupper 3 ,
.Xr isxdigit 3 ,
.Xr stdio 3 ,
.Xr toascii 3 ,
.Xr toupper 3 ,
.Xr ascii 7
.Sh STANDARDS
The
.Fn tolower
function conforms to
.St -ansiC .