CTYPE(3)                                                 CTYPE(3)

     NAME
          isalpha, isupper, islower, isdigit, isalnum, isspace,
          ispunct, isprint, iscntrl, isascii - character
          classification

     SYNOPSIS
          #include <ctype.h>        isalnum(c)

          isalpha(c)                      isspace(c)

          isupper(c)                      ispunct(c)

          islower(c)                      isprint(c)

          isdigit(c)                      iscntrl(c)

                                          isascii(c)

    DESCRIPTION
         These macros classify ASCII-coded integer values by table
         lookup.  Each is a predicate returning nonzero for true,
         zero for false.  Isascii is defined on all integer values;
         the rest are defined only where isascii is true and on the
         single non-ASCII value EOF (see stdio(3)).

         isalpha  c is a letter

         isupper  c is an upper case letter

         islower  c is a lower case letter

         isdigit  c is a digit

         isalnum  c is an alphanumeric character

         isspace  c is a space, tab, carriage return, newline, or
                  formfeed

         ispunct  c is a punctuation character (neither control nor
                  alphanumeric)

         isprint  c is a printing character, code 040 octal (space)
                  through 0176 (tilde)

         iscntrl  c is a delete character (0177) or ordinary control
                  character (less than 040).

         isascii  c is an ASCII character, i.e.  0≦c<0200.

    SEE ALSO

    CTYPE(3)                                                 CTYPE(3)

         tolower(3), ascii(7)