- The function new_fieldtype creates a new field type usable for data
+ The function new_fieldtype creates a new field type usable for data
validation. Its parameters are function pointers:
- field_check
+ field_check
This function checks the validity of an entered data string
whenever the user attempts to leave a field. It has two
arguments:
- o The (FIELD *) argument is passed in so the validation
+ o The (FIELD *) argument is passed in so the validation
predicate can see the field's buffer, sizes and other
attributes.
- o The second argument is an argument-block structure, about
+ o The second argument is an argument-block structure, about
which more below.
- char_check
+ char_check
This function validates input characters as they are entered. The
form library passes it the character to be checked and a pointer
to an argument-block structure.
- The free_fieldtype function frees the space allocated for a given
- validation type by new_fieldtype.
+ The free_fieldtype function frees the space allocated for a given
+ validation type by new_fieldtype.
- The function set_fieldtype_arg associates three storage-management
+ The function set_fieldtype_arg associates three storage-management
functions with a field type:
- make_arg
+ make_arg
This function is automatically applied to the list of arguments
- you give set_field_type when attaching validation to a field. It
+ you give set_field_type when attaching validation to a field. It
stores the arguments in an allocated argument-block object which
is used when validating input.
- copy_arg
+ copy_arg
This function may be used by applications to copy argument-blocks.
- free_arg
+ free_arg
Frees an argument-block structure.
- You must supply the make_arg function. The other two are optional: you
+ You must supply the make_arg function. The other two are optional: you
may supply NULL for them. In this case, the form library assumes that
- make_arg does not allocate memory but simply loads the argument into a
+ make_arg does not allocate memory but simply loads the argument into a
single scalar value.
- The form driver requests REQ_NEXT_CHOICE and REQ_PREV_CHOICE assume
+ The form driver requests REQ_NEXT_CHOICE and REQ_PREV_CHOICE assume
that the possible values of a field form an ordered set, and provide
the forms user with a way to move through the set.
- The set_fieldtype_choice function allows forms programmers to define
+ The set_fieldtype_choice function allows forms programmers to define
successor and predecessor functions for the field type. These
functions take the field pointer and an argument-block structure as
arguments.
- The function link_fieldtype creates a new field type from the two given
+ The function link_fieldtype creates a new field type from the two given
types. They are connected by an logical 'OR'.
- The pointer-valued routines return NULL on error. They set errno
+ The pointer-valued routines return NULL on error. They set errno
according to their success:
- E_OK The routine succeeded.
+ E_OK The routine succeeded.
- E_BAD_ARGUMENT
+ E_BAD_ARGUMENT
Routine detected an incorrect or out-of-range argument.
- E_SYSTEM_ERROR
+ E_SYSTEM_ERROR
System error occurred, e.g., malloc failure.
The integer-valued routines return one of the following codes on error:
- E_OK The routine succeeded.
+ E_OK The routine succeeded.
- E_BAD_ARGUMENT
+ E_BAD_ARGUMENT
Routine detected an incorrect or out-of-range argument.
- E_CONNECTED
+ E_CONNECTED
The field is already connected to a form.
- E_CURRENT
+ E_CURRENT
The field is the current field.
- E_SYSTEM_ERROR
- System error occurred (see errno(3)).
+ E_SYSTEM_ERROR
+ System error occurred (see errno(3)).
- The header file <form.h> automatically includes the header file
- <curses.h>.
+ The header file <form.h> automatically includes the header file
+ <curses.h>.