RFC 885 (rfc885) - Page 2 of 2
Telnet end of record option
Alternative Format: Original Text Document
RFC 885 December 1983
4. Motivation for the Option
Many interactive systems use one (or more) of the normal data
characters to indicate the end of an effective unit of data (i.e., a
record), for example, carriage-return (or line-feed, or escape).
Some systems, however, have some special means of indicating the end
of an effective data unit, for example, a special key. This Telnet
option provides a means of communicating the end of data unit in a
standard way.
5. Description of the Option
When the END-OF-RECORD option is in effect on the connection between
a sender of data and the receiver of the data, the sender transmits
EORs.
It seems probable that the parties to the Telnet connection will
transmit EORs in both directions of the Telnet connection if EORs are
used at all; however, the use of EORs must be negotiated
independently for each direction.
When the END-OF-RECORD option is not in effect, the IAC EOR command
should be treated as a NOP if received, although IAC EOR should not
normally be sent in this mode.
6. Implementation Considerations
As the EOR code indicates the end of an effective data unit, Telnet
should attempt to send the data up to and including the EOR code
together to promote communication efficiency.
The end of record is indicated by the IAC EOR 2-octet sequence. The
code for EOR is 239 (decimal).
Postel