conv(3C) LIBRARY FUNCTIONS conv(3C)
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 argu-
ment 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, andtolower are affected by
LCCTYPE. 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 charac-
ters are returned unchanged.
SEE ALSO
ctype(3C), getc(3S), setlocale(3C), environ(5).
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