FORMS(3)						   BSD Library Functions Manual 						  FORMS(3)

NAME

     free_fieldtype, link_fieldtype, new_fieldtype, set_fieldtype_arg, set_fieldtype_choice -- form library

LIBRARY

     Curses Form Library (libform, -lform)

SYNOPSIS

     #include <form.h>

     int
     free_fieldtype(FIELDTYPE *fieldtype);

     FIELDTYPE *
     link_fieldtype(FIELDTYPE *type1, FIELDTYPE *type2);

     FIELDTYPE *
     new_fieldtype(int (*field_check)(FIELD *, char *), int (*char_check)(int, char *));

     int
     set_fieldtype_arg(FIELDTYPE *fieldtype, char * (*make_args)(va_list *), char * (*copy_args)(char *), void (*free_args)(char *));

     int
     set_fieldtype_choice(FIELDTYPE *fieldtype, int (*next_choice)(FIELD *, char *), int (*prev_choice)(FIELD *, char *));

DESCRIPTION

     The function free_fieldtype() frees the storage associated with the field type and destroys it.  The function link_fieldtype() links together
     the two given field types to produce a new field type.  A new field type can be created by calling new_fieldtype() which requires pointers to
     two functions which perform validation, the field_check function must validate the field contents and return TRUE if they are acceptable and
     FALSE if they are not.  The char_check validates the character input into the field, this function will be called for each character entered,
     if the character can be entered into the field then char_check must return TRUE.  Neither field_check nor char_check may be NULL.	The func-
     tions for handling the field type arguments can be defined by using the set_fieldtype_arg() function, the make_args function is used to cre-
     ate new arguments for the fieldtype, the copy_args is used to copy the fieldtype arguments to a new arguments structure and free_args is used
     to destroy the fieldtype arguments and release any associated storage, none of these function pointers may be NULL.  The field type choice
     functions can be set by calling set_fieldtype_choice(), the next_choice and prev_choice specify the next and previous choice functions for
     the field type.  These functions must perform the necessary actions to select the next or previous choice for the field, updating the field
     buffer if necessary.  The choice functions must return TRUE if the function succeeded and FALSE otherwise.

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:

     E_OK		The function was successful.
     E_BAD_ARGUMENT	The function was passed a bad argument.
     E_CONNECTED	The field is connected to a form.

SEE ALSO

     curses(3), forms(3)

NOTES

     The header <form.h> automatically includes both <curses.h> and <eti.h>.

BSD
								  January 1, 2001							       BSD