NAME

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 domain the range of getc(3S): the integers from −1 through 255. If the argument of toupper() represents a lowercase letter, the result is the corresponding uppercase letter.  If the argument of tolower() represents an uppercase letter, the result is the corresponding lowercase letter.  All other arguments in the domain are returned unchanged.  Arguments outside the domain cause undefined results. 

The macros _toupper() and _tolower() perform the same translations as toupper() and tolower(), but have restricted domains and are faster.  The domains of _toupper() and _tolower() are the integers from 0 through 255.  Arguments outside of 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. 

WARNING

toascii() is supplied both as a library function and as a macro defined in the <ctype.h> header.  Normally, the macro version is used.  To obtain the library function, either use a #undef to remove the macro definition or, if compiling in ANSI C mode, enclose the function name in parenthesis or take its address.  The following examples use the library function for toascii():

#include <ctype.h>
#undef toascii
...
main()
{
...
    c1 = toascii(c);
...
}

or

#include <ctype.h>
...
main()
{
   int (*conv_func)();
...
   c1 = (toascii)(c);
...
   conv_func = toascii;
...
}

EXTERNAL INFLUENCES

Locale

The LC_CTYPE category determines the translations to be done. 

International Code Set Support

Single-byte character code sets are supported. 

AUTHOR

conv() was developed by AT&T and HP. 

SEE ALSO

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

STANDARDS CONFORMANCE

_tolower(): AES, SVID2, XPG2, XPG3, XPG4

_toupper(): AES, SVID2, XPG2, XPG3, XPG4

toascii(): AES, SVID2, XPG2, XPG3, XPG4

tolower(): AES, SVID2, XPG2, XPG3, XPG4, FIPS 151-2, POSIX.1, ANSI C

toupper(): AES, SVID2, XPG2, XPG3, XPG4, FIPS 151-2, POSIX.1, ANSI C

Hewlett-Packard Company  —  HP-UX Release 9.0: August 1992