.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved 
.TH "TOLOWER" 3P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual"
.\" tolower 
.SH PROLOG
This manual page is part of the POSIX Programmer's Manual.
The Linux implementation of this interface may differ (consult
the corresponding Linux manual page for details of Linux behavior),
or the interface may not be implemented on Linux.
.SH NAME
tolower \- transliterate uppercase characters to lowercase
.SH SYNOPSIS
.LP
\fB#include <ctype.h>
.br
.sp
int tolower(int\fP \fIc\fP\fB);
.br
\fP
.SH DESCRIPTION
.LP
The \fItolower\fP() function has as a domain a type \fBint\fP, the
value of which is representable as an \fBunsigned char\fP
or the value of EOF. If the argument has any other value, the behavior
is undefined. If the argument of \fItolower\fP() represents
an uppercase letter, and there exists a corresponding lowercase letter
\ (as defined by character type information in the program
locale category \fILC_CTYPE ),\fP  the result shall be the
corresponding lowercase letter. All other arguments in the domain
are returned unchanged.
.SH RETURN VALUE
.LP
Upon successful completion, \fItolower\fP() shall return the lowercase
letter corresponding to the argument passed; otherwise,
it shall return the argument unchanged.
.SH ERRORS
.LP
No errors are defined.
.LP
\fIThe following sections are informative.\fP
.SH EXAMPLES
.LP
None.
.SH APPLICATION USAGE
.LP
None.
.SH RATIONALE
.LP
None.
.SH FUTURE DIRECTIONS
.LP
None.
.SH SEE ALSO
.LP
\fIsetlocale\fP(), the Base Definitions volume of IEEE\ Std\ 1003.1-2001,
Chapter 7, Locale, \fI<ctype.h>\fP
.SH COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group. In the
event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online at
http://www.opengroup.org/unix/online.html .