man7.org > Linux > man-pages

Linux/UNIX system programming training

form_variables(3x) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | PORTABILITY | SEE ALSO | COLOPHON 

form_variables(3X)            Library calls            form_variables(3X)

NAME         top

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

SYNOPSIS         top

       #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         top

       These are building blocks for the form library, defining fields
       that can be created using the form_fieldtype(3X) functions.  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         top

       The TYPE_IPV4 variable is an extension not provided by older
       implementations of the form library.

SEE ALSO         top

       form(3X)

COLOPHON         top

       This page is part of the ncurses (new curses) project.
       Information about the project can be found at 
       ⟨https://invisible-island.net/ncurses/ncurses.html⟩.  If you have a
       bug report for this manual page, send it to bug-ncurses@gnu.org.
       This page was obtained from the tarball ncurses-6.6.tar.gz fetched
       from ⟨https://ftp.gnu.org/gnu/ncurses/⟩ on 2026-01-16.  If you
       discover any rendering problems in this HTML version of the page,
       or you believe there is a better or more up-to-date source for the
       page, or you have corrections or improvements to the information
       in this COLOPHON (which is not part of the original manual page),
       send a mail to man-pages@man7.org

ncurses @NCURSES_MAJOR@.@NCU... 2024-03-16             form_variables(3X)

HTML rendering created 2026-01-16 by Michael Kerrisk, author of The Linux Programming Interface.

For details of in-depth Linux/UNIX system programming training courses that I teach, look here.

Hosting by jambit GmbH.

Cover of TLPI