# form_variables 3x

    form_variables(3x)                                          form_variables(3x)

## NAME

           TYPE_ALNUM, TYPE_ALPHA, TYPE_ENUM, TYPE_INTEGER, TYPE_IPV4,
           TYPE_NUMERIC, TYPE_REGEXP - form system global variables

## SYNOPSIS

           #include <form.h>

           FIELDTYPE * TYPE_ALNUM;
           FIELDTYPE * TYPE_ALPHA;
           FIELDTYPE * TYPE_ENUM;
           FIELDTYPE * TYPE_INTEGER;
           FIELDTYPE * TYPE_IPV4;
           FIELDTYPE * TYPE_NUMERIC;
           FIELDTYPE * TYPE_REGEXP;

## DESCRIPTION

           These are building blocks for the form library,  defining  fields  that
           can  be  created  using set_fieldtype(3x).  Each provides functions for
           field- and character-validation, according to the given datatype.

### TYPE_ALNUM

           This holds alphanumeric data.

### TYPE_ALPHA

           This holds alphabetic data.

### TYPE_ENUM

           This holds an enumerated type.

### TYPE_INTEGER

           This holds a decimal integer.

### TYPE_IPV4

           This holds an IPv4 internet address, e.g., "127.0.0.1".

### TYPE_NUMERIC

           This holds a decimal number, with optional sign and decimal point.

### TYPE_REGEXP

           This holds a regular expression.

## PORTABILITY

           The TYPE_IPV4 variable is an extension not provided by older  implemen-
           tations of the form library.

## SEE ALSO

           form(3x).

                                                                form_variables(3x)