form_init

form_hook(3X)							form_hook(3X)



NAME
       form_hook - set hooks for automatic invocation by applications

SYNOPSIS
       #include <form.h>
       int set_field_init(FORM *form, void (*func)(FORM *));
       void (*)(FORM *) field_init(const FORM *form);
       int set_field_term(FORM *form, void (*func)(FORM *));
       void (*)(FORM *) field_term(const FORM *form);
       int set_form_init(FORM *form, void (*func)(FORM *));
       void (*)(FORM *) form_init(const FORM *form);
       int set_form_term(FORM *form, void (*func)(FORM *));
       void (*)(FORM *) form_term(const FORM *form);

DESCRIPTION
       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.

       The function 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).

       The function 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).

       The  function 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).

       The  function  set_form_term  sets  a hook to be called at form-unpost
       time and just before a page  change  once  it  is  posted.   form_init
       returns	the  current form term hook, if any (NULL if there is no such
       hook).

RETURN VALUE
       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).

SEE ALSO
       curses(3X), form(3X).

NOTES
       The  header  file  <form.h>  automatically  includes  the  header file
       <curses.h>.

PORTABILITY
       These routines emulate the System V forms library.  They were not sup-
       ported on Version 7 or BSD versions.

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



								form_hook(3X)