Alphanumeric data. Requires a third int argument, a minimum field width.
TYPE_ALPHA
Character data. Requires a third int argument, a minimum field width.
TYPE_ENUM
Accept one of a specified set of strings. Requires a third (char **) argument pointing to a string list; a fourth int flag argument to enable case-sensitivity; and a fifth int flag argument specifying whether a partial match must be a unique one (if this flag is off, a prefix matches the first of any set of more than one list elements with that prefix). Please notice that the string list is not copied, only a reference to it is stored in the field. So you should avoid to use a list that lives in automatic variables on the stack.
TYPE_INTEGER
Integer data, parsable to an integer by atoi(3). Requires a third int argument controlling the precision, a fourth long argument constraining minimum value, and a fifth long constraining maximum value. If the maximum value is less or equal the minimum value, the range is simply ignored. On return the field buffer is formatted according to the printf format specification ".*ld", where the * is replaced by the precision argument. For details of the precision handling see printfs man-page.
TYPE_NUMERIC
Numeric data (may have a decimal-point part). Requires a third int argument controlling the precision, a fourth double argument constraining minimum value, and a fifth double constraining maximum value. If your system supports locales, the decimal point character to be used must be the one specified by your locale. If the maximum value is less or equal the minimum value, the range is simply ignored. On return the field buffer is formatted according to the printf format specification ".*f", where the * is replaced by the precision argument. For details of the precision handling see printfs man-page.
TYPE_REGEXP
Regular expression data. Requires a regular expression (char *) third argument; the data is valid if the regular expression matches it. Regular expressions are in the format of regcomp(3X) and regexec(3X). Please notice that the regular expression must match the whole field. If you have for example an eight character wide field, a regular expression "^[0-9]*$" always means that you have to fill all eight positions with digits. If you want to allow fewer digits, you may use for example "^[0-9]* *$" which is good for trailing spaces (up to an empty field), or "^ *[0-9]* *$" which is good for leading and trailing spaces around the digits.
TYPE_IPV4
An Internet Protocol Version 4 address. This requires no additional argument. It is checked whether or not the buffer has the form a.b.c.d, where a,b,c and d are numbers between 0 and 255. Trailing blanks in the buffer are ignored. The address itself is not validated. Please note that this is an ncurses extension. This field type may not be available in other curses implementations.
It is possible to set up new programmer-defined field types. See the form_fieldtype(3X) manual page.