NCctype

Purpose

     Classify characters  for international  character support
     environments.

Syntax

     #include <NLctype.h>

     int NCisNLchar  (x)                |      int NCisalnum  (x)
     int x;                             |      int x;
                                        |
     int NCisalpha  (x)                 |      int NCisspace  (x)
     int x;                             |      int x;
                                        |
     int NCisupper  (x)                 |      int NCispunct  (x)
     int x;                             |      int x;
                                        |
     int NCislower  (x)                 |      int NCisprint  (x)
     int x;                             |      int x;
                                        |
     int NCisdigit  (x)                 |      int NCisgraph  (x)
     int x;                             |      int x;
                                        |
     int NCisxdigit  (x)                |      int NCiscntrl  (x)
     int x;                             |      int x;
                                        |
                                        |      int NCisshift  (x)
                                        |      int x;
     Description

     Character   classification   is   user-configurable   per
     process, through the table file indicated by the environ-
     ment variable NLCTAB.

     These  macros  classify  character-coded  integer  values
     using information  specified by  the current  NLCTAB file
     configuration.  The  parameter x  is tested as  an NLchar
     (an extended  character); each macro is  a predicate form
     returning 0  for false,  and a  non-zero value  for true.
     The value of x is in the  domain of any legal NLchar in a
     value range from 0 to NLCHARMAX-1 inclusive, or a special
     value of -1.  If  the value of x is not  in the domain of
     the macro, the result is undefined.

     The  NCisNLchar macro  is  defined on  all valid  integer
     values, whereas  the other macros are  defined only where
     NCisNLchar is true, and on the special value of -1 (EOF).
     See "standard i/o library."

     When a non-zero value is returned for x:

     NCisNLchar   x is a  valid NLchar with a  value between 0
                  and NLCHARMAX-1, inclusive.

     NCisalpha    x is an alphabetical character.

     NCisupper    x is an uppercase alphabetical character.

     NCislower    x is a lowercase letter.

     NCisdigit    x is a decimal digit (0-9).

     NCisxdigit   x  is  a  hexadecimal digit  (0-9,  A-F  (or
                  a-f)).

     NCisalnum    x is an alphanumeric character or digit.

     NCisspace    x  is a  space, tab,  carriage return,  new-
                  line, vertical tab, or form-feed character.

     NCispunct    x  is  a  punctuation character  (neither  a
                  control character nor  an alphanumeric char-
                  acter).

     NCisprint    x  is a  printing  character (including  the
                  space character).

     NCisgraph    x  is a  printing  character, excluding  the
                  space character.

     NCiscntrl    x is an ASCII  delete character (0177) or an
                  ordinary ASCII control  character other than
                  the four single-shift characters.

     NCisshift    x is one of the four single-shift characters
                  that  is  used  as  the  first  byte  of  an
                  extended character.

     Related Information

     In this  book:  "conv," "ctype,"  "getc,  fgetc, getchar,
     getw," "NLchar,"   "standard i/o library,"  and "environ-
     ment."

     "Overview of International Character Support" in Managing
     the AIX Operating System.