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

form_hook(3X)                                                  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.

       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         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).

SEE ALSO         top

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

NOTES         top

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

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.

COLOPHON         top

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                                                               form_hook(3X)