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form_hook(3x) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | PORTABILITY | AUTHORS | SEE ALSO | COLOPHON 

form_hook(3X)                 Library calls                 form_hook(3X)

NAME         top

       form_hook - set hooks for automatic invocation by applications

SYNOPSIS         top

       #include <form.h>

       int set_field_init(FORM *form, Form_Hook func);
       Form_Hook field_init(const FORM *form);

       int set_field_term(FORM *form, Form_Hook func);
       Form_Hook field_term(const FORM *form);

       int set_form_init(FORM *form, Form_Hook func);
       Form_Hook form_init(const FORM *form);

       int set_form_term(FORM *form, Form_Hook func);
       Form_Hook form_term(const FORM *form);

DESCRIPTION         top

       These functions make it possible to set hook functions to be
       called at various points in the automatic processing of input
       event codes by form_driver.

   set_field_init
       sets a hook to be called at form-post time and each time the
       selected field changes (after the change).

   field_init
       returns the current field init hook, if any (NULL if there is no
       such hook).

   set_field_term
       sets a hook to be called at form-unpost time and each time the
       selected field changes (before the change).

   field_term
       returns the current field term hook, if any (NULL if there is no
       such hook).

   set_form_init
       sets a hook to be called at form-post time and just after a page
       change once it is posted.

   form_init
       returns the current form init hook, if any (NULL if there is no
       such hook).

   set_form_term
       sets a hook to be called at form-unpost time and just before a
       page change once it is posted.

   form_term
       returns the current form term hook, if any (NULL if there is no
       such hook).

RETURN VALUE         top

       Routines that return pointers return NULL on error.  Other
       routines return one of the following:

       E_OK The routine succeeded.

       E_SYSTEM_ERROR
            System error occurred (see errno(3)).

PORTABILITY         top

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

AUTHORS         top

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

SEE ALSO         top

       curses(3X), form(3X)

COLOPHON         top

       This page is part of the ncurses (new curses) project.
       Information about the project can be found at 
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       bug report for this manual page, send it to bug-ncurses@gnu.org.
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ncurses @NCURSES_MAJOR@.@NCU... 2024-12-28                  form_hook(3X)

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