Apple Newton Programmer’s Newton 2.0 (for Newton 2.0) - Manual (Page 843)

C H A P T E R 2 3
Endpoint Interface
Using the Endpoint Interface 23-15
termination sequence, or an array of items, any one of which will cause the input to
terminate. A termination sequence can be a single character, a string, a number, or
an array of bytes. If you don't want to look for a termination sequence, don't define
this slot.
For the 'binary data form, you cannot use the endSequence slot to specify a
termination condition.
Note
Note that the system executes byte-by-byte comparisons between
the termination sequence and the input stream. To facilitate this
process, the termination sequence (or elements within the
endSequence array) is converted to a byte or binary format to
speed the comparison. Internally, single characters are converted
to single bytes using the translation table specified by the
endpoint
encoding slot. Numbers are converted to single bytes;
strings are converted to binary objects. An array of bytes is also
treated as a binary object. For large numbers, you must encode
your number as an array of bytes if there are significant digits
beyond the high order byte of the number.
◆
If you want to terminate input based on a transport-level end-of-packet (EOP)
indicator, then you can set the
useEOP slot in the termination frame. This slot
holds a Boolean value specifying whether or not to look for EOP indicators.
Specify this slot only if the input spec
rcvFlags slot includes the kPacket flag.
Moreover, if the rcvFlags slot includes the kPacket flag and you do not specify
the termination.useEOP slot, the system effectively sets useEOP to the
default value true . For more information, see the following section, “Specifying
Flags for Receiving.”
It is not appropriate to specify the termination slot for data forms other than
'string , 'bytes , and 'binary . The 'char and 'number data forms
automatically terminate after 1 and 4 bytes, respectively. The 'frame data form is
terminated automatically when a complete frame has been received, and the
'template data form terminates when the number of bytes received matches the
typelist specification in the target frame.
To limit the amount of accumulated data in the input buffer, you can define a
discardAfter slot in the input spec. You can do this only when you have not
specified a termination.byteCount slot for 'string and 'bytes data
forms. The discardAfter slot sets the input buffer size. If the buffer overflows,
older bytes are discarded in favor of more recently received bytes.