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<H1 class="no-header">form 3x</H1>
<PRE>
<STRONG><A HREF="form.3x.html">form(3x)</A></STRONG>                                                              <STRONG><A HREF="form.3x.html">form(3x)</A></STRONG>


</PRE><H2><a name="h2-NAME">NAME</a></H2><PRE>
       <STRONG>form</STRONG> - curses extension for programming forms


</PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
       <STRONG>#include</STRONG> <STRONG>&lt;form.h&gt;</STRONG>


</PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
       The <STRONG>form</STRONG> 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  <STRONG>form</STRONG>  library uses the <STRONG>curses</STRONG> libraries.  To use the <STRONG>form</STRONG> library,
       link with the options <STRONG>-lform</STRONG> <STRONG>-lcurses</STRONG>.

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

            <STRONG>setlocale(LC_ALL,</STRONG> <STRONG>"");</STRONG>

       so that input/output processing will work.

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


</PRE><H3><a name="h3-Current-Default-Values-for-Field-Attributes">Current Default Values for Field Attributes</a></H3><PRE>
       The  <STRONG>form</STRONG>  library maintains a default value for field attributes.  You
       can get or  set  this  default  by  calling  the  appropriate  <STRONG>set_</STRONG>  or
       retrieval  routine  with  a  <STRONG>NULL</STRONG> field pointer.  Changing this default
       with a <STRONG>set_</STRONG> function affects  future  field  creations,  but  does  not
       change the rendering of fields already created.


</PRE><H3><a name="h3-Routine-Name-Index">Routine Name Index</a></H3><PRE>
       The  following table lists each <STRONG>form</STRONG> routine and the name of the manual
       page on which it is described.  Routines flagged with "*" are  ncurses-
       specific, not present in SVr4.

       <STRONG>curses</STRONG> Routine Name     Manual Page Name
       --------------------------------------------------
       current_field           <STRONG><A HREF="form_page.3x.html">form_page(3x)</A></STRONG>
       data_ahead              <STRONG><A HREF="form_data.3x.html">form_data(3x)</A></STRONG>
       data_behind             <STRONG><A HREF="form_data.3x.html">form_data(3x)</A></STRONG>
       dup_field               <STRONG><A HREF="form_field_new.3x.html">form_field_new(3x)</A></STRONG>
       dynamic_field_info      <STRONG><A HREF="form_field_info.3x.html">form_field_info(3x)</A></STRONG>
       field_arg               <STRONG><A HREF="form_field_validation.3x.html">form_field_validation(3x)</A></STRONG>
       field_back              <STRONG><A HREF="form_field_attributes.3x.html">form_field_attributes(3x)</A></STRONG>
       field_buffer            <STRONG><A HREF="form_field_buffer.3x.html">form_field_buffer(3x)</A></STRONG>
       field_count             <STRONG><A HREF="form_field.3x.html">form_field(3x)</A></STRONG>
       field_fore              <STRONG><A HREF="form_field_attributes.3x.html">form_field_attributes(3x)</A></STRONG>
       field_index             <STRONG><A HREF="form_page.3x.html">form_page(3x)</A></STRONG>
       field_info              <STRONG><A HREF="form_field_info.3x.html">form_field_info(3x)</A></STRONG>
       field_init              <STRONG><A HREF="form_hook.3x.html">form_hook(3x)</A></STRONG>
       field_just              <STRONG><A HREF="form_field_just.3x.html">form_field_just(3x)</A></STRONG>
       field_opts              <STRONG><A HREF="form_field_opts.3x.html">form_field_opts(3x)</A></STRONG>
       field_opts_off          <STRONG><A HREF="form_field_opts.3x.html">form_field_opts(3x)</A></STRONG>
       field_opts_on           <STRONG><A HREF="form_field_opts.3x.html">form_field_opts(3x)</A></STRONG>
       field_pad               <STRONG><A HREF="form_field_attributes.3x.html">form_field_attributes(3x)</A></STRONG>
       field_status            <STRONG><A HREF="form_field_buffer.3x.html">form_field_buffer(3x)</A></STRONG>
       field_term              <STRONG><A HREF="form_hook.3x.html">form_hook(3x)</A></STRONG>
       field_type              <STRONG><A HREF="form_field_validation.3x.html">form_field_validation(3x)</A></STRONG>
       field_userptr           <STRONG><A HREF="form_field_userptr.3x.html">form_field_userptr(3x)</A></STRONG>

       form_driver             <STRONG><A HREF="form_driver.3x.html">form_driver(3x)</A></STRONG>
       form_driver_w           <STRONG><A HREF="form_driver.3x.html">form_driver(3x)</A></STRONG>*
       form_fields             <STRONG><A HREF="form_field.3x.html">form_field(3x)</A></STRONG>
       form_init               <STRONG><A HREF="form_hook.3x.html">form_hook(3x)</A></STRONG>
       form_opts               <STRONG><A HREF="form_opts.3x.html">form_opts(3x)</A></STRONG>
       form_opts_off           <STRONG><A HREF="form_opts.3x.html">form_opts(3x)</A></STRONG>
       form_opts_on            <STRONG><A HREF="form_opts.3x.html">form_opts(3x)</A></STRONG>
       form_page               <STRONG><A HREF="form_page.3x.html">form_page(3x)</A></STRONG>
       form_request_by_name    <STRONG><A HREF="form_requestname.3x.html">form_requestname(3x)</A></STRONG>*
       form_request_name       <STRONG><A HREF="form_requestname.3x.html">form_requestname(3x)</A></STRONG>*
       form_sub                <STRONG><A HREF="form_win.3x.html">form_win(3x)</A></STRONG>
       form_term               <STRONG><A HREF="form_hook.3x.html">form_hook(3x)</A></STRONG>
       form_userptr            <STRONG><A HREF="form_userptr.3x.html">form_userptr(3x)</A></STRONG>
       form_win                <STRONG><A HREF="form_win.3x.html">form_win(3x)</A></STRONG>
       free_field              <STRONG><A HREF="form_field_new.3x.html">form_field_new(3x)</A></STRONG>
       free_fieldtype          <STRONG><A HREF="form_fieldtype.3x.html">form_fieldtype(3x)</A></STRONG>
       free_form               <STRONG><A HREF="form_new.3x.html">form_new(3x)</A></STRONG>
       link_field              <STRONG><A HREF="form_field_new.3x.html">form_field_new(3x)</A></STRONG>
       link_fieldtype          <STRONG><A HREF="form_fieldtype.3x.html">form_fieldtype(3x)</A></STRONG>
       move_field              <STRONG><A HREF="form_field.3x.html">form_field(3x)</A></STRONG>
       new_field               <STRONG><A HREF="form_field_new.3x.html">form_field_new(3x)</A></STRONG>
       new_fieldtype           <STRONG><A HREF="form_fieldtype.3x.html">form_fieldtype(3x)</A></STRONG>
       new_form                <STRONG><A HREF="form_new.3x.html">form_new(3x)</A></STRONG>
       new_page                <STRONG><A HREF="form_new_page.3x.html">form_new_page(3x)</A></STRONG>
       pos_form_cursor         <STRONG><A HREF="form_cursor.3x.html">form_cursor(3x)</A></STRONG>
       post_form               <STRONG><A HREF="form_post.3x.html">form_post(3x)</A></STRONG>
       scale_form              <STRONG><A HREF="form_win.3x.html">form_win(3x)</A></STRONG>
       set_current_field       <STRONG><A HREF="form_page.3x.html">form_page(3x)</A></STRONG>
       set_field_back          <STRONG><A HREF="form_field_attributes.3x.html">form_field_attributes(3x)</A></STRONG>
       set_field_buffer        <STRONG><A HREF="form_field_buffer.3x.html">form_field_buffer(3x)</A></STRONG>
       set_field_fore          <STRONG><A HREF="form_field_attributes.3x.html">form_field_attributes(3x)</A></STRONG>
       set_field_init          <STRONG><A HREF="form_hook.3x.html">form_hook(3x)</A></STRONG>
       set_field_just          <STRONG><A HREF="form_field_just.3x.html">form_field_just(3x)</A></STRONG>
       set_field_opts          <STRONG><A HREF="form_field_opts.3x.html">form_field_opts(3x)</A></STRONG>
       set_field_pad           <STRONG><A HREF="form_field_attributes.3x.html">form_field_attributes(3x)</A></STRONG>
       set_field_status        <STRONG><A HREF="form_field_buffer.3x.html">form_field_buffer(3x)</A></STRONG>
       set_field_term          <STRONG><A HREF="form_hook.3x.html">form_hook(3x)</A></STRONG>
       set_field_type          <STRONG><A HREF="form_field_validation.3x.html">form_field_validation(3x)</A></STRONG>
       set_field_userptr       <STRONG><A HREF="form_field_userptr.3x.html">form_field_userptr(3x)</A></STRONG>
       set_fieldtype_arg       <STRONG><A HREF="form_fieldtype.3x.html">form_fieldtype(3x)</A></STRONG>
       set_fieldtype_choice    <STRONG><A HREF="form_fieldtype.3x.html">form_fieldtype(3x)</A></STRONG>
       set_form_fields         <STRONG><A HREF="form_field.3x.html">form_field(3x)</A></STRONG>
       set_form_init           <STRONG><A HREF="form_hook.3x.html">form_hook(3x)</A></STRONG>
       set_form_opts           <STRONG><A HREF="form_field_opts.3x.html">form_field_opts(3x)</A></STRONG>
       set_form_page           <STRONG><A HREF="form_page.3x.html">form_page(3x)</A></STRONG>
       set_form_sub            <STRONG><A HREF="form_win.3x.html">form_win(3x)</A></STRONG>
       set_form_term           <STRONG><A HREF="form_hook.3x.html">form_hook(3x)</A></STRONG>
       set_form_userptr        <STRONG><A HREF="form_userptr.3x.html">form_userptr(3x)</A></STRONG>
       set_form_win            <STRONG><A HREF="form_win.3x.html">form_win(3x)</A></STRONG>
       set_max_field           <STRONG><A HREF="form_field_buffer.3x.html">form_field_buffer(3x)</A></STRONG>
       set_new_page            <STRONG><A HREF="form_new_page.3x.html">form_new_page(3x)</A></STRONG>
       unfocus_current_field   <STRONG><A HREF="form_page.3x.html">form_page(3x)</A></STRONG>*
       unpost_form             <STRONG><A HREF="form_post.3x.html">form_post(3x)</A></STRONG>


</PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
       Routines  that  return  pointers return <STRONG>NULL</STRONG> on error, and set <STRONG>errno</STRONG> to
       the  corresponding  error-code  returned  by  functions  returning   an
       integer.   Routines  that return an integer return one of the following
       error codes:

       <STRONG>E_OK</STRONG> The routine succeeded.

       <STRONG>E_BAD_ARGUMENT</STRONG>
            Routine detected an incorrect or out-of-range argument.

       <STRONG>E_BAD_STATE</STRONG>
            Routine was called from an initialization or termination function.

       <STRONG>E_CONNECTED</STRONG>
            The field is already connected to a form.

       <STRONG>E_INVALID_FIELD</STRONG>
            Contents of a field are not valid.

       <STRONG>E_NOT_CONNECTED</STRONG>
            No fields are connected to the form.

       <STRONG>E_NOT_POSTED</STRONG>
            The form has not been posted.

       <STRONG>E_NO_ROOM</STRONG>
            Form is too large for its window.

       <STRONG>E_POSTED</STRONG>
            The form is already posted.

       <STRONG>E_REQUEST_DENIED</STRONG>
            The form driver could not process the request.

       <STRONG>E_SYSTEM_ERROR</STRONG>
            System error occurred (see <STRONG>errno(3)</STRONG>).

       <STRONG>E_UNKNOWN_COMMAND</STRONG>
            The form driver code saw an unknown request code.


</PRE><H2><a name="h2-NOTES">NOTES</a></H2><PRE>
       The header  file  <STRONG>&lt;form.h&gt;</STRONG>  automatically  includes  the  header  files
       <STRONG>&lt;curses.h&gt;</STRONG> and <STRONG>&lt;eti.h&gt;</STRONG>.

       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 libraries).


</PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
       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 <EM>Character</EM> <EM>User</EM>  <EM>Interface</EM>
       <EM>Programming</EM> <EM>(UNIX</EM> <EM>SVR4.2)</EM>.

       It is not part of X/Open Curses.

       Aside from ncurses, there are few implementations:

       <STRONG>o</STRONG>   systems based on SVr4 source code, e.g., Solaris.

       <STRONG>o</STRONG>   NetBSD curses.

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


</PRE><H2><a name="h2-AUTHORS">AUTHORS</a></H2><PRE>
       Juergen  Pfeifer.   Manual  pages and adaptation for ncurses by Eric S.
       Raymond.


</PRE><H2><a name="h2-SEE-ALSO">SEE ALSO</a></H2><PRE>
       <STRONG><A HREF="ncurses.3x.html">curses(3x)</A></STRONG> and related pages whose names  begin  "form_"  for  detailed
       descriptions of the entry points.

       This describes <STRONG>ncurses</STRONG> version 6.3 (patch 20211021).


                                                                      <STRONG><A HREF="form.3x.html">form(3x)</A></STRONG>
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<ul>
<li><a href="#h3-Current-Default-Values-for-Field-Attributes">Current Default Values for Field Attributes</a></li>
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</ul>
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