TOUPPER(3)

NAME
toupper - lower case to upper case letter conversion

SYNOPSIS
#include <ctype.h>
int
toupper(int c);

DESCRIPTION
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.

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

STANDARDS
The toupper() function conforms to ansiC.