rfc1053.txt

著名的RFC文档,其中有一些文档是已经翻译成中文的的.

     Output lines may be folded (e.g., by insertion of carriage return
     and line feed) when they exceed a specified width.

     Code 0 -- No output line folding.
     Codes 1 through 255 -- Fold lines after that many characters.

Parameter 11 -- Bit rate.

     This parameter indicates the serial data rate of the user's
     terminal, if any.  Though CCITT X.3 considers this parameter to be
     read-only, it may be meaningful to allow the host to set as well as
     read this value, thus changing the user's line speed dynamically.

     Code 0 -- 110 bps            Code 10 -- 50 bps
     Code 1 -- 134.5 bps          Code 11 -- 75 bps in, 1200 out
     Code 2 -- 300 bps            Code 12 -- 2400 bps
     Code 3 -- 1200 bps           Code 13 -- 4800 bps
     Code 4 -- 600 bps            Code 14 -- 9600 bps
     Code 5 -- 75 bps             Code 15 -- 19200 bps
     Code 6 -- 150 bps            Code 16 -- 48000 bps
     Code 7 -- 1800 bps           Code 17 -- 56000 bps
     Code 8 -- 200 bps            Code 18 -- 64000 bps
     Code 9 -- 100 bps



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RFC 1053                 Telnet X.3 PAD Option                April 1988


Parameter 12 -- Flow control of host-to-user data.

     When this parameter is 1, the user may type X-OFF (DC3, ASCII code
     19) to suspend printing output, and X-ON (DC1, ASCII code 17) to
     resume output.

     Code 0 -- X-OFF and X-ON are sent as data to host.
     Code 1 -- X-OFF and X-ON control output.

     See also the extension parameters 130, 131 and 132.

Parameter 13 -- Line feed insertion; Telnet CR LF vs CR NUL.

     The CCITT uses this parameter to select whether a typed CR should
     be sent as CR or CR-LF, whether an output CR should have a LF
     printed after it, and whether an echoed CR should be echoed with an
     accompanying LF.

     Here, it resolves the questions of mapping between the Telnet CR-LF
     sequence and single ASCII codes (i.e., when the user presses the
     carriage return key, should CR LF or CR NUL be sent to the host?
     When the host sends CR LF, should the user see CR LF or merely CR?)

     The value is bit-encoded; codes may be added to select multiple
     functions.

     Code 0 -- No line feed insertion
               (typed CR sent as CR NUL; host CR LF printed as CR).
     Code 1 -- Add line feed on output (host CR LF printed as CR LF).
     Code 2 -- Add line feed on input (typed CR sent as CR LF to host).
     Code 4 -- When echoing a typed CR locally, echo as CR LF.

     Note the interaction with the TRANSMIT-BINARY Telnet option [5].
     If the host has said WILL TRANSMIT-BINARY, then CR has no special
     meaning on output; it always stands for the single character CR
     regardless of this parameter's value.  If the user telnet has said
     WILL TRANSMIT-BINARY, a typed CR should likewise always be sent as
     itself and not as CR LF or CR NUL.

Parameter 14 -- Output padding after line feed.

     Gives the number of ASCII NUL padding characters to be sent to the
     user's terminal after each output line feed.

     Codes 0 through 7 -- Send that many padding characters.






Levy & Jacobson                                                [Page 12]

RFC 1053                 Telnet X.3 PAD Option                April 1988


Parameter 15 -- Local editing.

     If this parameter is 1, the character delete, line delete and line
     reprint functions (parameters 16, 17 and 18), if implemented,
     should be enabled.  Data should be sent to the host when a
     forwarding character (see parameter 3) is typed or in case the user
     telnet's input buffer becomes full.

     Note the interaction with parameter 4, Forward after idle time.
     User telnets need not handle the case where idle-time forwarding
     and local editing are both enabled, i.e., the host should
     explicitly request changing parameter 4 to 0 along with setting
     parameter 15 to 1.

     Code 0 -- No input editing.  Any editing characters are considered
               data.
     Code 1 -- Input editing.  Editing characters edit the input buffer.

Parameter 16 -- Character-delete character.

     While local editing (parameter 15) is enabled, typing this
     character erases the last character in the editing buffer, if any.
     When editing is disabled, this character is not treated specially.

     Code 0 -- No character has this function.
     Codes 1 through 127 -- ASCII code of character-delete character.

     See also parameter 19.

Parameter 17 -- Line-delete character.

     While local editing (parameter 15) is enabled, this character
     erases the entire contents of the editing buffer.  When editing is
     disabled, this character is not treated specially.

     Code 0 -- No character has this function.
     Codes 1 through 127 -- ASCII code of line-delete character.

     See also parameter 19.

Parameter 18 -- Line-display character.

     While local editing (parameter 15) is enabled, typing this
     character causes the current contents of the editing buffer to be
     printed on the user's terminal; nothing is sent to the host.  When
     editing is disabled, this character is not treated specially.

     Code 0 -- No character has this function.



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RFC 1053                 Telnet X.3 PAD Option                April 1988


     Codes 1 through 127 -- ASCII code of line-display character.

Parameter 19 -- Editing service signals.

     This determines what is echoed to the user when local editing is
     enabled and the character-delete or line-delete character is
     entered.

     Code 0 -- Nothing is echoed.
     Code 1 -- Editing style is suitable for printing terminals.
     Code 2 -- Editing style is suitable for display terminals.
     Codes 8 and 32-126 -- Echo that ASCII character for
               character-delete.

     X.3 is specific on handling character- and line-deletion.  If
     parameter 19 is 1, echo character-delete with a "line delete with
     three X's followed by CR LF.  If 2, a character-delete echoes BS
     SPACE BS, while a line delete echoes enough BS SPACE BS's to erase
     the entire line.  If 8 or 32-126, character-delete echoes that
     character, and line delete echoes XXX CR LF.  An extension
     parameter could override these, selecting other styles if desired,
     though none is proposed here.

Parameter 20 -- Echo mask.

     When local echoing, parameter 2, is enabled, each nonzero bit in
     this bit-encoded parameter's value suppresses echoing of some
     subset of ASCII characters.  Adding values suppresses echo for the
     union of the specified subsets.

     Code 0   --  all ASCII characters are echoed.
     Code 1   --  CR is not echoed.
     Code 2   --  LF is not echoed.
     Code 4   --  VT, HT, and FF are not echoed.
     Code 8   --  BEL and BS are not echoed.
     Code 16  --  ESC and ENQ are not echoed.
     Code 32  --  ACK, NAK, STX, SOH, EOT, ETB and ETX are not echoed.
     Code 64  --  Editing characters are not echoed.
     Code 128 --  other non-printing ASCII characters, and DEL, not
                  echoed.

     Nothing is echoed when parameter 2 is 0.  Some characters should
     not be echoed regardless of parameter 20.  If any of parameters 5,
     12, or 22 are enabled (non-zero), then the XON and XOFF characters
     should not be echoed.  Nor should the escape-to-local command mode
     character, parameter 1.





Levy & Jacobson                                                [Page 14]

RFC 1053                 Telnet X.3 PAD Option                April 1988


Parameter 21 -- Parity.

     This parameter determines whether parity is checked on user input
     and generated on output to the user.  Values may be added to select
     both.

     Code 0 -- Parity neither generated nor checked.
     Code 1 -- Even parity checked on input.
     Code 2 -- Even parity generated on output.

Parameter 22 -- Page wait.

     If enabled, this parameter causes the user telnet to pause after
     every N lines of output as if X-OFF had been received.  Output
     resumes when X-ON is typed.

     Code 0 -- No pause.
     Codes 1-255 -- Pause after output of that many line feeds.

     See also parameters 130, 131 and 132.

The following parameters are not part of CCITT X.3, but use the
extension mechanism proposed for this Telnet option.

Parameter 128 -- Extension set number.

     This parameter selects one of a potentially large number of
     "extension sets" -- more or less coherent collections of parameters
     added to the basic X.3 family.  User telnets may support several
     extension sets.  The host may determine whether a particular one is
     supported by trying to set parameter 128.  The user telnet should
     accept the value if it provides some or all of the parameters in
     that set.

     Extension sets might be defined for a variety of purposes.  For
     example, Berkeley UNIX tty emulation, VMS emulation, Telenet's
     extended parameters, French national PDN parameters, and so on.

     Initial values need not be specified for extension parameters
     (i.e., a host should explicitly negotiate for their values after
     selecting an extension set).  However, it is recommended that
     default settings give service that resembles normal CCITT X.3
     behavior where possible.

     Extension sets are mutually exclusive.  Different sets may use the
     same parameters (from 129 through 255) for different purposes.

     Only one extension set is in effect at a time.  That is, if a host



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RFC 1053                 Telnet X.3 PAD Option                April 1988


     requests service X from extension set A, then switches to extension
     set B and requests its service Y, it should not expect that service
     X is still being provided.

     Some values of this parameter are reserved:

     Code 0 -- Null extension set.  Only (a subset of) the basic CCITT
                 X.3 parameters is provided.  Every user telnet should
                 accept this setting.
     Code 1 -- (A subset of) the extension set 1 parameters described
                 below is provided.
     Code 255 -- Reserved for purely local (e.g., to a site), non-
                 standard collections of extensions.

     Other extension sets may be proposed and assigned set numbers in
     the range 2 through 254.

          Set number are registered with the Internet Assigned Numbers
          Coordinator at USC-ISI.  Please contact:

               Joyce K. Reynolds
               USC Information Sciences Institute
               Suite 1001
               4676 Admiralty Way
               Marina del Rey, CA  90292-6695

               213-822-1511   [e-mail]

The following parameters form extension set number 1.

Parameter 129, extension set 1 -- Word-delete character.

     Typing this character while local editing is enabled causes the
     last word in the editing buffer to be erased.  Several definitions
     for a "word" are in common use; this RFC does not specify one.
     There should be an indication to the user of what was erased.  When
     editing is disabled, this character is not treated specially.

     Code 0 -- No character has this function.