| TOUPPER(3) | Library Functions Manual | TOUPPER(3) |
toupper — lower
case to upper case letter conversion
Standard C Library (libc, -lc)
#include
<ctype.h>
int
toupper(int
c);
The
toupper()
function converts a lower-case letter to the corresponding upper-case
letter.
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.
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)
The toupper() function conforms to
ANSI X3.159-1989
(“ANSI C89”).
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.
| April 17, 2008 | NetBSD 11.0 |