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TOLOWER(3)                 Library Functions Manual                 TOLOWER(3)

NAME
     tolower - upper case to lower case letter conversion

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <ctype.h>

     int
     tolower(int c);

DESCRIPTION
     The tolower() function converts an upper-case letter to the corresponding
     lower-case letter.

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.

SEE ALSO
     ctype(3), isalnum(3), isalpha(3), isascii(3), iscntrl(3), isdigit(3),
     isgraph(3), islower(3), isprint(3), ispunct(3), isspace(3), isupper(3),
     isxdigit(3), stdio(3), toascii(3), toupper(3), ascii(7)

STANDARDS
     The tolower() function conforms to ANSI X3.159-1989 ("ANSI C89").

CAVEATS
     The argument to tolower() must be EOF or representable as an unsigned
     char; otherwise, the behavior is undefined.  See the CAVEATS section of
     ctype(3) for more details.

NetBSD 10.99                    April 17, 2008                    NetBSD 10.99