NAME

toupper, tolower, _toupper, _tolower, toascii − translate characters

SYNOPSIS

#include <ctype.h>

int toupper (c)
int c;

int tolower (c)
int c;

int _toupper (c)
int c;

int _tolower (c)
int c;

int toascii (c)
int c;

DESCRIPTION

Toupper and tolower have as domain the range of getc(3S): the integers from −1 through 255. If the argument of toupper represents a lower-case letter, the result is the corresponding upper-case letter.  If the argument of tolower represents an upper-case letter, the result is the corresponding lower-case letter.  All other arguments in the domain are returned unchanged. 

_toupper and _tolower are macros that accomplish the same thing as toupper and tolower but have restricted domains and are faster.  _toupper requires a lower-case letter as its argument; its result is the corresponding upper-case letter.  _tolower requires an upper-case letter as its argument; its result is the corresponding lower-case letter.  Arguments outside the domain cause undefined results. 

Toascii yields its argument with all bits turned off that are not part of a standard ASCII character; it is intended for compatibility with other systems. 

SEE ALSO

ctype(3C), getc(3S). 

Version 2.4  —  May 08, 1986