form_fieldtype(3curses)

form_fieldtype: new_fieldtype, free_fieldtype, set_fieldtype_arg, set_fieldtype_choice, link_fieldtype -- forms fieldtype routines

Synopsis

   cc [flag . . .] file -lform -lcurses [library . . .] 
    
   #include <form.h> 
   
 
   FIELDTYPE new_fieldtype(int ( field_check)(FIELD , char ), 
   	int ( char_check)(int, char )); 
   int free_fieldtype(FIELDTYPE fieldtype); 
   int set_fieldtype_arg(FIELDTYPE fieldtype, 
   	char ( mak_arg)(va_list ), 
   	char ( copy_arg)(char ), void ( free_arg)(char )); 
   int set_fieldtype_choice(FIELDTYPE fieldtype, 
   	int ( next_choice)(FIELD , char ), 
   	int ( prev_choice)(FIELD , char )); 
   FIELDTYPE link_fieldtype(FIELDTYPE type1, FIELDTYPE type2);

Description

new_fieldtype creates a new field type. The application programmer must write the function field_check, which validates the field value, and the function char_check, which validates each character. free_fieldtype frees the space allocated for the field type.

By associating function pointers with a field type, set_fieldtype_arg connects to the field type additional arguments necessary for a set_field_type call. Function mak_arg allocates a structure for the field specific parameters to set_field_type and returns a pointer to the saved data. Function copy_arg duplicates the structure created by mak_arg. Function free_arg frees any storage allocated by mak_arg or copy_arg.

The form_driver requests REN_NEXT_CHOICE and REQ_PREV_CHOICE let the user request the next or previous value of a field type comprising an ordered set of values. set_fieldtype_choice allows the application programmer to implement these requests for the given field type. It associates with the given field type those application-defined functions that return pointers to the next or previous choice for the field.

link_fieldtype returns a pointer to the field type built from the two given types. The constituent types may be any application-defined or pre-defined types.

<Return> value

Routines that return pointers always return NULL on error. Routines that return an integer return one of the following:

E_OK The function returned successfully.

E_SYSTEM_ERROR System error.

E_BAD_ARGUMENT An argument is incorrect.

E_CONNECTED Type is connected to one or more fields.

Notices

The header file form.h automatically includes the header files eti.h and curses.h.

References

curses(3curses), forms(3curses)

E_OK	The function returned successfully.
E_SYSTEM_ERROR	System error.
E_BAD_ARGUMENT	An argument is incorrect.
E_CONNECTED	Type is connected to one or more fields.