.\"	$NetBSD: form_hook.3,v 1.1 2001/07/08 12:10:29 blymn Exp $
.\"
.\" Copyright (c) 2001
.\"	Brett Lymn - blymn@baea.com.au, brett_lymn@yahoo.com.au
.\"
.\" This code is donated to The NetBSD Foundation by the author.
.\"
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.\"    products derived from this software without specific prior written
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.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND
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.Dd January, 2001
.Dt FORMS 3
.Os 
.Sh NAME
.Nm field_init ,
.Nm field_term ,
.Nm form_init ,
.Nm form_term ,
.Nm set_field_init ,
.Nm set_field_term ,
.Nm set_form_init ,
.Nm set_form_term
.Nd form library
.Sh LIBRARY
.Lb libform
.Sh SYNOPSIS
.Fd #include <form.h>
.Ft void (*)(FORM *)
.Fn field_init "FORM *form"
.Ft void (*)(FORM *)
.Fn field_term "FORM *form"
.Ft void (*)(FORM *)
.Fn form_init "FORM *form"
.Ft void (*)(FORM *)
.Fn form_term "FORM *form"
.Ft int
.Fn set_field_init "FORM *form, void (*function)(FORM *)"
.Ft int
.Fn set_field_term "FORM *form, void (*function)(FORM *)"
.Ft int
.Fn set_form_init "FORM *form, void (*function)(FORM *)"
.Ft int
.Fn set_form_term "FORM *form, void (*function)(FORM *)"
.Sh DESCRIPTION
The 
.Fn field_init
function returns a pointer to the function that will be called just
after the current field changes and just before the form is posted,
this function may be set by using the 
.Fn set_field_init
function.  Similarly, the function
.Fn field_term
will return a pointer to the function that will be called just before
the current field changes and just after the form is unposted, this
function pointer may be set by using the
.Fn set_field_term
function.  The
.Fn form_init
function will return a pointer to the function that will be called
just before the form is posted to the screen, this function can be set
by calling the 
.Fn set_form_init
function.  The 
.Fn form_term
function will return a pointer to the function that will be called
just after the form is unposted from the screen, this function may be
set by using the
.Fn set_form_term
function.  By default, the init and term function pointers are NULL.
.Sh RETURN VALUES
Functions returning pointers will return NULL if an error is detected.
The functions that return an int will return one of the following error
values:
.Pp
.Bl -tag -width E_UNKNOWN_COMMAND -compact
.It Er E_OK
The function was successful.
.El
.Sh SEE ALSO
.Xr curses 3 ,
.Xr forms 3
.Sh NOTES
The header
.Pa <form.h>
automatically includes both
.Pa <curses.h>
and
.Pa <eti.h> .