CONV(3C-SVR4)       RISC/os Reference Manual        CONV(3C-SVR4)



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

SEE ALSO
     ctype(3C-SVR4), getc(3S-SVR4), setlocale(3C-SVR4),
     environ(5-SVR4).





                        Printed 11/19/92                   Page 1