EN JA
form_hook(3X)
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, 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

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 supported on Version 7 or BSD versions.

AUTHORS

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