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 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.  Arguments outside the domain cause undefined results. 

The macros _toupper() and _tolower() are identical to toupper() and tolower(), respectively. 

toascii() yields its argument with all bits that are not part of a standard 7-bit ASCII character cleared; 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;
...
}

The following example use the library function for toupper():

#include <ctype.h>
#undef toupper
...
main()
{
...
char *c;
*c=toupper ((unsigned char*) c);
...
}

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 IBM, OSF, and HP. 

SEE ALSO

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

STANDARDS CONFORMANCE

_tolower(): AES, SVID2, SVID3, XPG2, XPG3, XPG4

_toupper(): AES, SVID2, SVID3, XPG2, XPG3, XPG4

toascii(): AES, SVID2, SVID3, XPG2, XPG3, XPG4

tolower(): AES, SVID2, SVID3, XPG2, XPG3, XPG4, FIPS 151-2, POSIX.1, ANSI C

toupper(): AES, SVID2, SVID3, XPG2, XPG3, XPG4, FIPS 151-2, POSIX.1, ANSI C

Hewlett-Packard Company  —  HP-UX Release 10.20:  July 1996