form(3x) — Linux manual page


form(3X)                                                        form(3X)

NAME         top

       form - curses extension for programming forms

SYNOPSIS         top

       #include <form.h>

DESCRIPTION         top

       The form library provides terminal-independent facilities for
       composing form screens on character-cell terminals.  The library
       includes: field routines, which create and modify form fields;
       and form routines, which group fields into forms, display forms
       on the screen, and handle interaction with the user.

       The form library uses the curses libraries.  To use the form
       library, link with the options -lform -lcurses.

       Your program should set up the locale, e.g.,

            setlocale(LC_ALL, "");

       so that input/output processing will work.

       A curses initialization routine such as initscr must be called
       before using any of these functions.

   Current Default Values for Field Attributes
       The form library maintains a default value for field attributes.
       You can get or set this default by calling the appropriate set_
       or retrieval routine with a NULL field pointer.  Changing this
       default with a set_ function affects future field creations, but
       does not change the rendering of fields already created.

   Routine Name Index
       The following table lists each form routine and the name of the
       manual page on which it is described.  Routines flagged with “*”
       are ncurses-specific, not present in SVr4.
       curses Routine Name     Manual Page Name
       current_field           form_page(3X)
       data_ahead              form_data(3X)
       data_behind             form_data(3X)
       dup_field               form_field_new(3X)
       dynamic_field_info      form_field_info(3X)
       field_arg               form_field_validation(3X)
       field_back              form_field_attributes(3X)
       field_buffer            form_field_buffer(3X)
       field_count             form_field(3X)
       field_fore              form_field_attributes(3X)
       field_index             form_page(3X)
       field_info              form_field_info(3X)
       field_init              form_hook(3X)
       field_just              form_field_just(3X)
       field_opts              form_field_opts(3X)
       field_opts_off          form_field_opts(3X)
       field_opts_on           form_field_opts(3X)
       field_pad               form_field_attributes(3X)
       field_status            form_field_buffer(3X)
       field_term              form_hook(3X)
       field_type              form_field_validation(3X)
       field_userptr           form_field_userptr(3X)
       form_driver             form_driver(3X)
       form_driver_w           form_driver(3X)*
       form_fields             form_field(3X)
       form_init               form_hook(3X)
       form_opts               form_opts(3X)
       form_opts_off           form_opts(3X)
       form_opts_on            form_opts(3X)
       form_page               form_page(3X)
       form_request_by_name    form_requestname(3X)*
       form_request_name       form_requestname(3X)*
       form_sub                form_win(3X)
       form_term               form_hook(3X)
       form_userptr            form_userptr(3X)
       form_win                form_win(3X)
       free_field              form_field_new(3X)
       free_fieldtype          form_fieldtype(3X)
       free_form               form_new(3X)
       link_field              form_field_new(3X)
       link_fieldtype          form_fieldtype(3X)
       move_field              form_field(3X)
       new_field               form_field_new(3X)
       new_fieldtype           form_fieldtype(3X)
       new_form                form_new(3X)
       new_page                form_new_page(3X)
       pos_form_cursor         form_cursor(3X)
       post_form               form_post(3X)
       scale_form              form_win(3X)
       set_current_field       form_page(3X)
       set_field_back          form_field_attributes(3X)
       set_field_buffer        form_field_buffer(3X)
       set_field_fore          form_field_attributes(3X)
       set_field_init          form_hook(3X)
       set_field_just          form_field_just(3X)
       set_field_opts          form_field_opts(3X)
       set_field_pad           form_field_attributes(3X)
       set_field_status        form_field_buffer(3X)
       set_field_term          form_hook(3X)
       set_field_type          form_field_validation(3X)
       set_field_userptr       form_field_userptr(3X)
       set_fieldtype_arg       form_fieldtype(3X)
       set_fieldtype_choice    form_fieldtype(3X)
       set_form_fields         form_field(3X)
       set_form_init           form_hook(3X)
       set_form_opts           form_field_opts(3X)
       set_form_page           form_page(3X)
       set_form_sub            form_win(3X)
       set_form_term           form_hook(3X)
       set_form_userptr        form_userptr(3X)
       set_form_win            form_win(3X)
       set_max_field           form_field_buffer(3X)
       set_new_page            form_new_page(3X)
       unfocus_current_field   form_page(3X)*
       unpost_form             form_post(3X)

RETURN VALUE         top

       Routines that return pointers return NULL on error, and set errno
       to the corresponding error-code returned by functions returning
       an integer.  Routines that return an integer return one of the
       following error codes:

       E_OK The routine succeeded.

            Routine detected an incorrect or out-of-range argument.

            Routine was called from an initialization or termination

            The field is already connected to a form.

            Contents of a field are not valid.

            No fields are connected to the form.

            The form has not been posted.

            Form is too large for its window.

            The form is already posted.

            The form driver could not process the request.

            System error occurred (see errno(3)).

            The form driver code saw an unknown request code.

NOTES         top

       The header file <form.h> automatically includes the header files
       <curses.h> and <eti.h>.

       In your library list, libform.a should be before libncurses.a;
       that is, you want to say “-lform -lncurses”, not the other way
       around (which would give you a link error when using static

PORTABILITY         top

       These routines emulate the System V forms library.  They were not
       supported on Version 7 or BSD versions.

       The menu facility was documented in SVr4.2 in Character User
       Interface Programming (UNIX SVR4.2).

       It is not part of X/Open Curses.

       Aside from ncurses, there are few implementations:

       •   systems based on SVr4 source code, e.g., Solaris.

       •   NetBSD curses.

       A few functions in this implementation are extensions added for
       ncurses, but not provided by other implementations, e.g.,
       form_driver_w, unfocus_current_field.

AUTHORS         top

       Juergen Pfeifer.  Manual pages and adaptation for ncurses by Eric
       S. Raymond.

SEE ALSO         top

       curses(3X) and related pages whose names begin “form_” for
       detailed descriptions of the entry points.

       This describes ncurses version @NCURSES_MAJOR@.@NCURSES_MINOR@
       (patch @NCURSES_PATCH@).

COLOPHON         top

       This page is part of the ncurses (new curses) project.
       Information about the project can be found at 
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       ⟨⟩ on 2023-12-22.  (At that
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