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TOUPPER(3)                 Library Functions Manual                 TOUPPER(3)

NAME
     toupper - lower case to upper case letter conversion

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <ctype.h>

     int
     toupper(int c);

DESCRIPTION
     The toupper() function converts a lower-case letter to the corresponding
     upper-case letter.

RETURN VALUES
     If the argument is a lower-case letter, the toupper() function returns
     the corresponding upper-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), ascii(7)

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

CAVEATS
     The argument to toupper() 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