NAME
tolower, tolower_l
— upper case to lower case
letter conversion
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include
<ctype.h>
int
tolower(int c);
#include <ctype.h>
#include <xlocale.h>
int
tolower_l(int c,
locale_t loc);
DESCRIPTION
The
tolower()
function converts an upper-case letter to the corresponding lower-case
letter. The argument must be representable as an unsigned
char or the value of EOF.
Although the
tolower()
function uses the current locale, the
tolower_l()
function may be passed a locale directly. See
xlocale(3) for more information.
RETURN VALUES
If the argument is an upper-case letter, the
tolower() function returns the corresponding
lower-case letter if there is one; otherwise, the argument is returned
unchanged.
COMPATIBILITY
The 4.4BSD extension of accepting
arguments outside of the range of the unsigned char
type in locales with large character sets is considered obsolete and may not
be supported in future releases. The towlower()
function should be used instead.
SEE ALSO
STANDARDS
The tolower() function conforms to
ISO/IEC 9899:1990
(“ISO C90”).