NAME

conv: toupper, tolower, _toupper, _tolower, toascii - translate characters

SYNOPSIS

#include <ctype.h>

int toupper (int c);

int tolower (int c);

int _toupper (int c);

int _tolower (int c);

int toascii (int c);

DESCRIPTION

toupper and tolower have as their domain the range of the function getc: all values represented in an unsigned char and the value of the macro EOF as defined in stdio.h. 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.

The macros _toupper and _tolower accomplish the same things as toupper and tolower, respectively, 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 7-bit ASCII character; it is intended for compatibility with other systems.

toupper, tolower, _toupper, and_tolower are affected by LC_CTYPE. In the C locale, or in a locale where shift information is not defined, these functions determine the case of characters according to the rules of the ASCII-coded character set. Characters outside the ASCII range of characters are returned unchanged.

SEE ALSO

ctype(3C), getc(3S), setlocale(3C), environ(5).