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TOLOWER(3)               BSD Library Functions Manual               TOLOWER(3)

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.  For sin-gle single
     gle C chars locales (see multibyte(3)), the value of the argument is 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
     ctype(3), islower(3), multibyte(3), towlower(3), xlocale(3)

STANDARDS
     The tolower() function conforms to ISO/IEC 9899:1990 (``ISO C90'').

BSD                             August 21, 2004                            BSD