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);

MT-LEVEL

MT-Safe with exceptions

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

NOTES

toupper, tolower, _toupper, _tolower and toascii can be used safely in a multi-thread application, as long as setlocale(3C) is not being called to change the locale. 

SunOS 5.5/SPARC  —  Last change: 22 Jan 1993