form - curses extension for programming forms


   #include <form.h>


   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.

   curses Routine Name    Manual Page Name
   current_field          page(3FORM)
   data_ahead             data(3FORM)
   data_behind            data(3FORM)
   dup_field              field_new(3FORM)
   dynamic_field_info     field_info(3FORM)
   field_arg              field_validation(3FORM)
   field_back             field_attributes(3FORM)
   field_buffer           field_buffer(3FORM)
   field_count            field(3FORM)
   field_fore             field_attributes(3FORM)
   field_index            page(3FORM)
   field_info             field_info(3FORM)
   field_init             hook(3FORM)
   field_just             field_just(3FORM)
   field_opts             field_opts(3FORM)
   field_opts_off         field_opts(3FORM)
   field_opts_on          field_opts(3FORM)
   field_pad              field_attributes(3FORM)
   field_status           field_buffer(3FORM)
   field_term             hook(3FORM)
   field_type             field_validation(3FORM)
   field_userptr          field_userptr(3FORM)
   form_driver            driver(3FORM)

   form_driver_w          driver(3FORM)*
   form_fields            field(3FORM)
   form_init              hook(3FORM)
   form_opts              opts(3FORM)
   form_opts_off          opts(3FORM)
   form_opts_on           opts(3FORM)
   form_page              page(3FORM)
   form_request_by_name   requestname(3FORM)
   form_request_name      requestname(3FORM)
   form_sub               win(3FORM)
   form_term              hook(3FORM)
   form_userptr           userptr(3FORM)
   form_win               win(3FORM)
   free_field             field_new(3FORM)
   free_fieldtype         fieldtype(3FORM)
   free_form              new(3FORM)
   link_field             field_new(3FORM)
   link_fieldtype         fieldtype(3FORM)
   move_field             field(3FORM)
   new_field              field_new(3FORM)
   new_fieldtype          fieldtype(3FORM)
   new_form               new(3FORM)
   new_page               new_page(3FORM)
   pos_form_cursor        cursor(3FORM)
   post_form              post(3FORM)
   scale_form             win(3FORM)
   set_current_field      page(3FORM)
   set_field_back         field_attributes(3FORM)
   set_field_buffer       field_buffer(3FORM)
   set_field_fore         field_attributes(3FORM)
   set_field_init         hook(3FORM)
   set_field_just         field_just(3FORM)
   set_field_opts         field_opts(3FORM)
   set_field_pad          field_attributes(3FORM)
   set_field_status       field_buffer(3FORM)
   set_field_term         hook(3FORM)
   set_field_type         field_validation(3FORM)
   set_field_userptr      field_userptr(3FORM)
   set_fieldtype_arg      fieldtype(3FORM)
   set_fieldtype_choice   fieldtype(3FORM)
   set_form_fields        field(3FORM)
   set_form_init          hook(3FORM)
   set_form_opts          field_opts(3FORM)
   set_form_page          page(3FORM)
   set_form_sub           win(3FORM)
   set_form_term          hook(3FORM)
   set_form_userptr       userptr(3FORM)
   set_form_win           win(3FORM)
   set_max_field          field_buffer(3FORM)
   set_new_page           new_page(3FORM)
   unpost_form            post(3FORM)


   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 function.

        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).

        The form driver code saw an unknown request code.


   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 using most linkers).


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


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


   ncurses(3NCURSES) and related  pages  whose  names  begin  "form_"  for
   detailed descriptions of the entry points.

   This describes ncurses version 6.0 (patch 20160625).



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