NAME

       tolower - transliterate uppercase characters to lowercase

SYNOPSIS

       #include <ctype.h>

       int tolower(int c);

DESCRIPTION

       The  tolower() function has as a domain a type int, the value of which is representable as
       an unsigned char or the value of EOF. If the argument has any other value, the behavior is
       undefined. If the argument of tolower() represents an uppercase letter, and there exists a
       corresponding lowercase letter  (as defined by character type information in  the  program
       locale  category  LC_CTYPE ),  the result shall be the corresponding lowercase letter. All
       other arguments in the domain are returned unchanged.

RETURN VALUE

       Upon successful completion, tolower() shall return the lowercase letter  corresponding  to
       the argument passed; otherwise, it shall return the argument unchanged.

ERRORS

       No errors are defined.

       The following sections are informative.

EXAMPLES

       None.

APPLICATION USAGE

       None.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       setlocale()  ,  the  Base  Definitions  volume of IEEE Std 1003.1-2001, Chapter 7, Locale,
       <ctype.h>

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 .