Fields
Fields name parts of a phrase for content manipulation in various ways.
field name = contents
-
name
is an identifier that refers to the field. -
contents
is any phrase structure, except that it cannot contain another field.
A field is used to:
- Delineate part of the data portion of the message.
- Indicate where outbound data is interpolated.
- Store a length-encoding.
Store an encoded phrase-check value. When a phrase is read (set up using
the hci_pd_receive
Tcl command), the corresponding
continuation is called with a keylist. The keylist associates the field names with the
input region that contains their value. When a phrase is written, the engine uses the
field’s value without regard to its content structure.
The restrictions on the field contents during reading do not apply when writing; you must ensure the protocol is satisfied.