TOUPPER(3) BSD 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. The argument must be representable as an
unsigned char or the value of EOF.
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.
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 towupper() function should be used instead.
SEE ALSO
ctype(3), isupper(3), towupper(3)
STANDARDS
The toupper() function conforms to ISO/IEC 9899:1990 (``ISO C90'').
BSD
July 25, 2010 BSD
