Annotation of src/usr.bin/telnet/telnet.1, Revision 1.39
1.39 ! jmc 1: .\" $OpenBSD: telnet.1,v 1.38 2007/03/15 22:51:16 jmc Exp $
1.2 niklas 2: .\" $NetBSD: telnet.1,v 1.5 1996/02/28 21:04:12 thorpej Exp $
3: .\"
1.1 deraadt 4: .\" Copyright (c) 1983, 1990, 1993
5: .\" The Regents of the University of California. All rights reserved.
6: .\"
7: .\" Redistribution and use in source and binary forms, with or without
8: .\" modification, are permitted provided that the following conditions
9: .\" are met:
10: .\" 1. Redistributions of source code must retain the above copyright
11: .\" notice, this list of conditions and the following disclaimer.
12: .\" 2. Redistributions in binary form must reproduce the above copyright
13: .\" notice, this list of conditions and the following disclaimer in the
14: .\" documentation and/or other materials provided with the distribution.
1.32 millert 15: .\" 3. Neither the name of the University nor the names of its contributors
1.1 deraadt 16: .\" may be used to endorse or promote products derived from this software
17: .\" without specific prior written permission.
18: .\"
19: .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20: .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21: .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22: .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23: .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24: .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25: .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26: .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27: .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28: .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29: .\" SUCH DAMAGE.
30: .\"
31: .\" from: @(#)telnet.1 8.4 (Berkeley) 2/3/94
32: .\"
1.39 ! jmc 33: .Dd $Mdocdate$
1.1 deraadt 34: .Dt TELNET 1
1.16 aaron 35: .Os
1.1 deraadt 36: .Sh NAME
37: .Nm telnet
1.16 aaron 38: .Nd user interface to the
1.1 deraadt 39: .Tn TELNET
40: protocol
41: .Sh SYNOPSIS
42: .Nm telnet
1.31 deraadt 43: .Bk -words
1.38 jmc 44: .Op Fl 468acdEFfKLrx
1.3 niklas 45: .Op Fl b Ar hostalias
1.1 deraadt 46: .Op Fl e Ar escapechar
47: .Op Fl k Ar realm
48: .Op Fl l Ar user
49: .Op Fl n Ar tracefile
1.38 jmc 50: .Op Fl X Ar authtype
1.1 deraadt 51: .Oo
52: .Ar host
1.9 deraadt 53: .Op Ar port
1.1 deraadt 54: .Oc
1.31 deraadt 55: .Ek
1.1 deraadt 56: .Sh DESCRIPTION
57: The
1.22 aaron 58: .Nm
1.1 deraadt 59: command
1.16 aaron 60: is used to communicate with another host using the
1.1 deraadt 61: .Tn TELNET
62: protocol.
63: If
1.22 aaron 64: .Nm
1.1 deraadt 65: is invoked without the
66: .Ar host
67: argument, it enters command mode,
68: indicated by its prompt
69: .Pq Nm telnet\&> .
70: In this mode, it accepts and executes the commands listed below.
71: If it is invoked with arguments, it performs an
72: .Ic open
73: command with those arguments.
74: .Pp
1.19 aaron 75: The options are as follows:
1.27 aaron 76: .Bl -tag -width Ds
1.37 otto 77: .It Fl 4
78: Forces
79: .Nm
80: to use IPv4 addresses only.
81: .It Fl 6
82: Forces
83: .Nm
84: to use IPv6 addresses only.
1.1 deraadt 85: .It Fl 8
1.22 aaron 86: Specifies an 8-bit data path.
87: This causes an attempt to negotiate the
1.1 deraadt 88: .Dv TELNET BINARY
89: option on both input and output.
90: .It Fl a
91: Attempt automatic login.
92: Currently, this sends the user name via the
93: .Ev USER
94: variable
95: of the
96: .Ev ENVIRON
97: option if supported by the remote system.
98: The name used is that of the current user as returned by
99: .Xr getlogin 2
100: if it agrees with the current user ID,
101: otherwise it is the name associated with the user ID.
1.3 niklas 102: .It Fl b Ar hostalias
103: Uses
104: .Xr bind 2
1.12 aaron 105: on the local socket to bind it to an aliased address (see
1.3 niklas 106: .Xr ifconfig 8
1.12 aaron 107: and the ``alias'' specifier) or to the address of
1.3 niklas 108: another interface than the one naturally chosen by
109: .Xr connect 2 .
1.12 aaron 110: This can be useful when connecting to services which use IP addresses
1.3 niklas 111: for authentication and reconfiguration of the server is undesirable (or
112: impossible).
1.1 deraadt 113: .It Fl c
114: Disables the reading of the user's
115: .Pa \&.telnetrc
1.22 aaron 116: file.
117: (See the
1.1 deraadt 118: .Ic toggle skiprc
119: command on this man page.)
120: .It Fl d
121: Sets the initial value of the
122: .Ic debug
123: toggle to
1.12 aaron 124: .Dv TRUE .
1.38 jmc 125: .It Fl E
126: Stops any character from being recognized as an escape character.
1.16 aaron 127: .It Fl e Ar escapechar
1.1 deraadt 128: Sets the initial
129: .Nm
130: escape character to
1.33 jmc 131: .Ar escapechar .
1.1 deraadt 132: If
1.8 deraadt 133: .Ar escapechar
1.1 deraadt 134: is omitted, then
135: there will be no escape character.
1.38 jmc 136: .It Fl F
137: If Kerberos authentication is being used, the
138: .Fl F
139: option allows the local credentials to be forwarded
140: to the remote system, including any credentials that
141: have already been forwarded into the local environment.
1.1 deraadt 142: .It Fl f
1.34 jmc 143: If Kerberos authentication is being used, the
1.1 deraadt 144: .Fl f
145: option allows the local credentials to be forwarded to the remote system.
1.38 jmc 146: .It Fl K
147: Specifies no automatic login to the remote system.
1.1 deraadt 148: .It Fl k Ar realm
149: If Kerberos authentication is being used, the
150: .Fl k
1.12 aaron 151: option requests that
1.22 aaron 152: .Nm
1.12 aaron 153: obtain tickets for the remote host in
1.8 deraadt 154: realm
155: .Ar realm
1.34 jmc 156: instead of the remote host's realm.
1.38 jmc 157: .It Fl L
158: Specifies an 8-bit data path on output.
159: This causes the BINARY option to be negotiated on output.
1.16 aaron 160: .It Fl l Ar user
1.1 deraadt 161: When connecting to the remote system, if the remote system
162: understands the
163: .Ev ENVIRON
164: option, then
165: .Ar user
166: will be sent to the remote system as the value for the variable USER.
167: This option implies the
168: .Fl a
169: option.
170: This option may also be used with the
171: .Ic open
172: command.
1.16 aaron 173: .It Fl n Ar tracefile
1.1 deraadt 174: Opens
175: .Ar tracefile
176: for recording trace information.
177: See the
178: .Ic set tracefile
179: command below.
180: .It Fl r
181: Specifies a user interface similar to
1.30 millert 182: .Nm rlogin .
1.1 deraadt 183: In this
184: mode, the escape character is set to the tilde (~) character,
1.8 deraadt 185: unless modified by the
186: .Fl e
187: option.
1.38 jmc 188: .It Fl X Ar authtype
189: Disables the
190: .Ar authtype
191: type of authentication.
1.1 deraadt 192: .It Fl x
1.33 jmc 193: Turn on encryption of the data stream.
194: When this option is turned on,
1.29 hin 195: .Nm
196: will exit with an error if authentication cannot be negotiated or if
197: encryption cannot be turned on.
1.1 deraadt 198: .It Ar host
199: Indicates the official name, an alias, or the Internet address
200: of a remote host.
201: .It Ar port
1.22 aaron 202: Indicates a port number (address of an application).
203: If a number is not specified, the default
204: .Nm
1.1 deraadt 205: port is used.
206: .El
207: .Pp
1.36 jmc 208: When in rlogin mode, a line of the form ~.\&
1.22 aaron 209: disconnects from the
1.1 deraadt 210: remote host; ~ is the telnet escape character.
211: Similarly, the line ~^Z suspends the telnet session.
212: The line ~^] escapes to the normal telnet escape prompt.
213: .Pp
214: Once a connection has been opened,
1.22 aaron 215: .Nm
1.1 deraadt 216: will attempt to enable the
217: .Dv TELNET LINEMODE
218: option.
1.12 aaron 219: If this fails,
1.22 aaron 220: .Nm
1.1 deraadt 221: will revert to one of two input modes:
1.12 aaron 222: either ``character at a time''
223: or ``old line by line''
1.1 deraadt 224: depending on what the remote system supports.
225: .Pp
1.16 aaron 226: When
1.1 deraadt 227: .Dv LINEMODE
228: is enabled, character processing is done on the
1.22 aaron 229: local system, under the control of the remote system.
230: When input
1.1 deraadt 231: editing or character echoing is to be disabled, the remote system
1.22 aaron 232: will relay that information.
233: The remote system will also relay
1.1 deraadt 234: changes to any special characters that happen on the remote
235: system, so that they can take effect on the local system.
236: .Pp
1.12 aaron 237: In ``character at a time'' mode, most
1.1 deraadt 238: text typed is immediately sent to the remote host for processing.
239: .Pp
1.12 aaron 240: In ``old line by line'' mode, all text is echoed locally,
1.1 deraadt 241: and (normally) only completed lines are sent to the remote host.
1.12 aaron 242: The ``local echo character'' (initially ``^E'') may be used
1.1 deraadt 243: to turn off and on the local echo
244: (this would mostly be used to enter passwords
245: without the password being echoed).
246: .Pp
1.16 aaron 247: If the
1.1 deraadt 248: .Dv LINEMODE
249: option is enabled, or if the
250: .Ic localchars
251: toggle is
252: .Dv TRUE
1.12 aaron 253: (the default for ``old line by line''; see below),
1.1 deraadt 254: the user's
1.12 aaron 255: .Ic quit ,
1.1 deraadt 256: .Ic intr ,
257: and
258: .Ic flush
259: characters are trapped locally, and sent as
260: .Tn TELNET
261: protocol sequences to the remote side.
1.16 aaron 262: If
1.1 deraadt 263: .Dv LINEMODE
264: has ever been enabled, then the user's
265: .Ic susp
266: and
267: .Ic eof
268: are also sent as
269: .Tn TELNET
270: protocol sequences,
271: and
272: .Ic quit
1.16 aaron 273: is sent as a
1.1 deraadt 274: .Dv TELNET ABORT
1.16 aaron 275: instead of
1.8 deraadt 276: .Dv BREAK .
1.1 deraadt 277: There are options (see
278: .Ic toggle
279: .Ic autoflush
280: and
281: .Ic toggle
282: .Ic autosynch
283: below)
284: which cause this action to flush subsequent output to the terminal
285: (until the remote host acknowledges the
286: .Tn TELNET
287: sequence) and flush previous terminal input
288: (in the case of
289: .Ic quit
290: and
1.22 aaron 291: .Ic intr ) .
1.1 deraadt 292: .Pp
293: While connected to a remote host,
1.22 aaron 294: .Nm
1.1 deraadt 295: command mode may be entered by typing the
1.22 aaron 296: .Nm
1.12 aaron 297: ``escape character'' (initially ``^]'').
1.1 deraadt 298: When in command mode, the normal terminal editing conventions are available.
1.15 aaron 299: Note that the escape character will return to the command mode of the initial
1.18 alex 300: invocation of
1.22 aaron 301: .Nm
1.23 aaron 302: that has the controlling terminal.
303: Use the
1.15 aaron 304: .Cm send escape
305: command to switch to command mode in subsequent
1.22 aaron 306: .Nm
1.15 aaron 307: processes on remote hosts.
1.1 deraadt 308: .Pp
309: The following
1.22 aaron 310: .Nm
1.1 deraadt 311: commands are available.
312: Only enough of each command to uniquely identify it need be typed
313: (this is also true for arguments to the
1.12 aaron 314: .Ic mode ,
1.1 deraadt 315: .Ic set ,
1.12 aaron 316: .Ic toggle ,
1.1 deraadt 317: .Ic unset ,
1.12 aaron 318: .Ic slc ,
1.1 deraadt 319: .Ic environ ,
320: and
321: .Ic display
322: commands).
323: .Bl -tag -width "mode type"
1.16 aaron 324: .It Ic auth Ar argument Op Ar ...
1.12 aaron 325: The
326: .Ic auth
327: command manipulates the information sent through the
1.1 deraadt 328: .Dv TELNET AUTHENTICATE
1.22 aaron 329: option.
330: Valid arguments for the
331: .Ic auth
332: command are as follows:
1.1 deraadt 333: .Bl -tag -width "disable type"
334: .It Ic disable Ar type
1.12 aaron 335: Disables the specified
336: .Ar type
1.22 aaron 337: of authentication.
338: To obtain a list of available types, use the
1.35 jmc 339: .Ic auth disable ?\&
1.1 deraadt 340: command.
341: .It Ic enable Ar type
1.12 aaron 342: Enables the specified
343: .Ar type
1.22 aaron 344: of authentication.
345: To obtain a list of available types, use the
1.35 jmc 346: .Ic auth enable ?\&
1.1 deraadt 347: command.
348: .It Ic status
349: Lists the current status of the various types of
350: authentication.
351: .El
352: .It Ic close
353: Close a
354: .Tn TELNET
355: session and return to command mode.
1.16 aaron 356: .It Ic display Ar argument Op Ar ...
1.1 deraadt 357: Displays all, or some, of the
358: .Ic set
359: and
360: .Ic toggle
361: values (see below).
1.12 aaron 362: .It Ic encrypt Ar argument Op Ar ...
363: The
364: .Ic encrypt
365: command manipulates the information sent through the
1.1 deraadt 366: .Dv TELNET ENCRYPT
1.28 hin 367: option that's available when Kerberos is used.
1.14 aaron 368: .Pp
1.1 deraadt 369: Valid arguments for the encrypt command are as follows:
370: .Bl -tag -width Ar
371: .It Ic disable Ar type Ic [input|output]
1.12 aaron 372: Disables the specified
373: .Ar type
1.22 aaron 374: of encryption.
375: If you omit
1.12 aaron 376: .Ic input
377: and
378: .Ic output ,
379: both input and output
1.22 aaron 380: are disabled.
381: To obtain a list of available types, use the
1.35 jmc 382: .Ic encrypt disable ?\&
1.1 deraadt 383: command.
384: .It Ic enable Ar type Ic [input|output]
1.12 aaron 385: Enables the specified
386: .Ar type
1.22 aaron 387: of encryption.
388: If you omit
1.12 aaron 389: .Ic input
390: and
391: .Ic output ,
392: both input and output are
1.22 aaron 393: enabled.
394: To obtain a list of available types, use the
1.35 jmc 395: .Ic encrypt enable ?\&
1.1 deraadt 396: command.
397: .It Ic input
398: This is the same as the
399: .Ic encrypt start input
400: command.
401: .It Ic -input
402: This is the same as the
403: .Ic encrypt stop input
404: command.
405: .It Ic output
406: This is the same as the
407: .Ic encrypt start output
408: command.
409: .It Ic -output
410: This is the same as the
411: .Ic encrypt stop output
412: command.
413: .It Ic start Ic [input|output]
1.22 aaron 414: Attempts to start encryption.
415: If you omit
1.1 deraadt 416: .Ic input
417: and
1.24 aaron 418: .Ic output ,
1.22 aaron 419: both input and output are enabled.
420: To obtain a list of available types, use the
1.35 jmc 421: .Ic encrypt enable ?\&
1.1 deraadt 422: command.
423: .It Ic status
424: Lists the current status of encryption.
425: .It Ic stop Ic [input|output]
1.22 aaron 426: Stops encryption.
427: If you omit
1.12 aaron 428: .Ic input
429: and
430: .Ic output ,
1.1 deraadt 431: encryption is on both input and output.
432: .It Ic type Ar type
433: Sets the default type of encryption to be used
434: with later
435: .Ic encrypt start
436: or
437: .Ic encrypt stop
438: commands.
439: .El
1.16 aaron 440: .It Ic environ Ar arguments Op Ar ...
1.1 deraadt 441: The
442: .Ic environ
443: command is used to manipulate the
1.11 deraadt 444: variables that may be sent through the
1.1 deraadt 445: .Dv TELNET ENVIRON
446: option.
447: The initial set of variables is taken from the users
448: environment, with only the
449: .Ev DISPLAY
450: and
451: .Ev PRINTER
452: variables being exported by default.
453: The
454: .Ev USER
455: variable is also exported if the
456: .Fl a
457: or
458: .Fl l
459: options are used.
1.38 jmc 460: .Pp
1.1 deraadt 461: Valid arguments for the
462: .Ic environ
463: command are:
464: .Bl -tag -width Fl
1.16 aaron 465: .It Ic define Ar variable value
1.1 deraadt 466: Define the variable
467: .Ar variable
468: to have a value of
1.12 aaron 469: .Ar value .
1.1 deraadt 470: Any variables defined by this command are automatically exported.
471: The
472: .Ar value
473: may be enclosed in single or double quotes so
474: that tabs and spaces may be included.
1.16 aaron 475: .It Ic undefine Ar variable
1.1 deraadt 476: Remove
477: .Ar variable
478: from the list of environment variables.
1.16 aaron 479: .It Ic export Ar variable
1.1 deraadt 480: Mark the variable
481: .Ar variable
482: to be exported to the remote side.
1.16 aaron 483: .It Ic unexport Ar variable
1.1 deraadt 484: Mark the variable
485: .Ar variable
486: to not be exported unless
487: explicitly asked for by the remote side.
488: .It Ic list
489: List the current set of environment variables.
490: Those marked with a
491: .Cm *
492: will be sent automatically,
493: other variables will only be sent if explicitly requested.
494: .It Ic \&?
495: Prints out help information for the
496: .Ic environ
497: command.
498: .El
499: .It Ic logout
500: Sends the
501: .Dv TELNET LOGOUT
502: option to the remote side.
503: This command is similar to a
504: .Ic close
505: command; however, if the remote side does not support the
506: .Dv LOGOUT
507: option, nothing happens.
508: If, however, the remote side does support the
509: .Dv LOGOUT
510: option, this command should cause the remote side to close the
511: .Tn TELNET
512: connection.
513: If the remote side also supports the concept of
514: suspending a user's session for later reattachment,
515: the logout argument indicates that you
516: should terminate the session immediately.
1.16 aaron 517: .It Ic mode Ar type
1.12 aaron 518: .Ar type
1.1 deraadt 519: is one of several options, depending on the state of the
520: .Tn TELNET
521: session.
522: The remote host is asked for permission to go into the requested mode.
523: If the remote host is capable of entering that mode, the requested
524: mode will be entered.
525: .Bl -tag -width Ar
526: .It Ic character
527: Disable the
528: .Dv TELNET LINEMODE
529: option, or, if the remote side does not understand the
530: .Dv LINEMODE
1.12 aaron 531: option, then enter ``character at a time'' mode.
1.1 deraadt 532: .It Ic line
533: Enable the
534: .Dv TELNET LINEMODE
535: option, or, if the remote side does not understand the
536: .Dv LINEMODE
1.12 aaron 537: option, then attempt to enter ``old-line-by-line'' mode.
1.16 aaron 538: .It Ic isig Pq Ic \-isig
539: Attempt to enable (disable) the
1.1 deraadt 540: .Dv TRAPSIG
1.16 aaron 541: mode of the
1.1 deraadt 542: .Dv LINEMODE
543: option.
1.16 aaron 544: This requires that the
1.1 deraadt 545: .Dv LINEMODE
546: option be enabled.
1.16 aaron 547: .It Ic edit Pq Ic \-edit
548: Attempt to enable (disable) the
1.1 deraadt 549: .Dv EDIT
1.16 aaron 550: mode of the
1.1 deraadt 551: .Dv LINEMODE
552: option.
1.16 aaron 553: This requires that the
1.1 deraadt 554: .Dv LINEMODE
555: option be enabled.
1.16 aaron 556: .It Ic softtabs Pq Ic \-softtabs
557: Attempt to enable (disable) the
1.1 deraadt 558: .Dv SOFT_TAB
1.16 aaron 559: mode of the
1.1 deraadt 560: .Dv LINEMODE
561: option.
1.16 aaron 562: This requires that the
1.1 deraadt 563: .Dv LINEMODE
564: option be enabled.
1.16 aaron 565: .It Ic litecho Pq Ic \-litecho
566: Attempt to enable (disable) the
1.1 deraadt 567: .Dv LIT_ECHO
1.16 aaron 568: mode of the
1.1 deraadt 569: .Dv LINEMODE
570: option.
1.16 aaron 571: This requires that the
1.1 deraadt 572: .Dv LINEMODE
573: option be enabled.
574: .It Ic \&?
575: Prints out help information for the
576: .Ic mode
577: command.
578: .El
579: .It Xo
580: .Ic open Ar host
1.5 deraadt 581: .Op Fl l Ar user
582: .Oo Op Fl
1.1 deraadt 583: .Ar port Oc
584: .Xc
585: Open a connection to the named host.
586: If no port number
587: is specified,
1.22 aaron 588: .Nm
1.1 deraadt 589: will attempt to contact a
590: .Tn TELNET
591: server at the default port.
592: The host specification may be either a host name (see
1.7 deraadt 593: .Xr hosts 5 )
1.12 aaron 594: or an Internet address specified in the ``dot notation'' (see
1.1 deraadt 595: .Xr inet 3 ) .
596: The
1.5 deraadt 597: .Fl l
1.1 deraadt 598: option may be used to specify the user name
599: to be passed to the remote system via the
600: .Ev ENVIRON
601: option.
602: When connecting to a non-standard port,
1.22 aaron 603: .Nm
1.1 deraadt 604: omits any automatic initiation of
605: .Tn TELNET
1.22 aaron 606: options.
607: When the port number is preceded by a minus sign,
1.1 deraadt 608: the initial option negotiation is done.
609: After establishing a connection, the file
610: .Pa \&.telnetrc
611: in the
1.22 aaron 612: user's home directory is opened.
613: Lines beginning with a ``#'' are
614: comment lines.
615: Blank lines are ignored.
616: Lines that begin
617: without whitespace are the start of a machine entry.
618: The first thing on the line is the name of the machine that is
619: being connected to.
620: The rest of the line, and successive
1.21 aaron 621: lines that begin with whitespace are assumed to be
1.22 aaron 622: .Nm
1.1 deraadt 623: commands and are processed as if they had been typed
624: in manually to the
1.22 aaron 625: .Nm
1.1 deraadt 626: command prompt.
627: .It Ic quit
628: Close any open
629: .Tn TELNET
630: session and exit
1.12 aaron 631: .Nm telnet .
632: An end-of-file (in command mode) will also close a session and exit.
1.16 aaron 633: .It Ic send Ar arguments
1.1 deraadt 634: Sends one or more special character sequences to the remote host.
635: The following are the arguments which may be specified
636: (more than one argument may be specified at a time):
637: .Bl -tag -width escape
638: .It Ic abort
639: Sends the
640: .Dv TELNET ABORT
641: (Abort
642: processes)
643: sequence.
644: .It Ic ao
645: Sends the
646: .Dv TELNET AO
647: (Abort Output) sequence, which should cause the remote system to flush
648: all output
649: .Em from
650: the remote system
651: .Em to
652: the user's terminal.
653: .It Ic ayt
654: Sends the
655: .Dv TELNET AYT
656: (Are You There)
657: sequence, to which the remote system may or may not choose to respond.
658: .It Ic brk
659: Sends the
660: .Dv TELNET BRK
661: (Break) sequence, which may have significance to the remote
662: system.
663: .It Ic ec
664: Sends the
665: .Dv TELNET EC
666: (Erase Character)
667: sequence, which should cause the remote system to erase the last character
668: entered.
669: .It Ic el
670: Sends the
671: .Dv TELNET EL
672: (Erase Line)
673: sequence, which should cause the remote system to erase the line currently
674: being entered.
675: .It Ic eof
676: Sends the
677: .Dv TELNET EOF
678: (End Of File)
679: sequence.
680: .It Ic eor
681: Sends the
682: .Dv TELNET EOR
683: (End of Record)
684: sequence.
685: .It Ic escape
686: Sends the current
1.22 aaron 687: .Nm
1.12 aaron 688: escape character (initially ``^]'').
1.1 deraadt 689: .It Ic ga
690: Sends the
691: .Dv TELNET GA
692: (Go Ahead)
693: sequence, which likely has no significance to the remote system.
694: .It Ic getstatus
695: If the remote side supports the
696: .Dv TELNET STATUS
697: command,
698: .Ic getstatus
699: will send the subnegotiation to request that the server send
700: its current option status.
701: .It Ic ip
702: Sends the
703: .Dv TELNET IP
704: (Interrupt Process) sequence, which should cause the remote
705: system to abort the currently running process.
706: .It Ic nop
707: Sends the
708: .Dv TELNET NOP
709: (No OPeration)
710: sequence.
711: .It Ic susp
712: Sends the
713: .Dv TELNET SUSP
714: (SUSPend process)
715: sequence.
716: .It Ic synch
717: Sends the
718: .Dv TELNET SYNCH
719: sequence.
720: This sequence causes the remote system to discard all previously typed
721: (but not yet read) input.
722: This sequence is sent as
723: .Tn TCP
724: urgent
725: data (and may not work if the remote system is a
726: .Bx 4.2
727: system -- if
1.12 aaron 728: it doesn't work, a lower case ``r'' may be echoed on the terminal).
1.1 deraadt 729: .It Ic do Ar cmd
1.12 aaron 730: Sends the
731: .Dv TELNET DO
732: .Ar cmd
733: sequence.
734: .Ar cmd
735: can be either a decimal number between 0 and 255,
736: or a symbolic name for a specific
737: .Dv TELNET
738: command.
739: .Ar cmd
740: can also be either
741: .Ic help
742: or
1.35 jmc 743: .Ic ?\&
1.12 aaron 744: to print out help information, including
745: a list of known symbolic names.
1.1 deraadt 746: .It Ic dont Ar cmd
1.12 aaron 747: Sends the
748: .Dv TELNET DONT
749: .Ar cmd
750: sequence.
751: .Ar cmd
752: can be either a decimal number between 0 and 255,
753: or a symbolic name for a specific
754: .Dv TELNET
755: command.
756: .Ar cmd
757: can also be either
758: .Ic help
759: or
1.35 jmc 760: .Ic ?\&
1.12 aaron 761: to print out help information, including
762: a list of known symbolic names.
1.1 deraadt 763: .It Ic will Ar cmd
1.12 aaron 764: Sends the
765: .Dv TELNET WILL
766: .Ar cmd
767: sequence.
768: .Ar cmd
769: can be either a decimal number between 0 and 255,
770: or a symbolic name for a specific
771: .Dv TELNET
772: command.
773: .Ar cmd
774: can also be either
775: .Ic help
776: or
1.35 jmc 777: .Ic ?\&
1.12 aaron 778: to print out help information, including
779: a list of known symbolic names.
1.1 deraadt 780: .It Ic wont Ar cmd
781: Sends the
1.12 aaron 782: .Dv TELNET WONT
1.1 deraadt 783: .Ar cmd
784: sequence.
1.12 aaron 785: .Ar cmd
1.1 deraadt 786: can be either a decimal number between 0 and 255,
787: or a symbolic name for a specific
788: .Dv TELNET
789: command.
1.12 aaron 790: .Ar cmd
1.1 deraadt 791: can also be either
792: .Ic help
793: or
1.35 jmc 794: .Ic ?\&
1.1 deraadt 795: to print out help information, including
796: a list of known symbolic names.
797: .It Ic \&?
798: Prints out help information for the
799: .Ic send
800: command.
801: .El
1.16 aaron 802: .It Ic set Ar argument value
803: .It Ic unset Ar argument value
1.1 deraadt 804: The
805: .Ic set
806: command will set any one of a number of
1.22 aaron 807: .Nm
1.1 deraadt 808: variables to a specific value or to
809: .Dv TRUE .
810: The special value
811: .Ic off
812: turns off the function associated with
1.12 aaron 813: the variable; this is equivalent to using the
1.1 deraadt 814: .Ic unset
815: command.
816: The
817: .Ic unset
818: command will disable or set to
819: .Dv FALSE
820: any of the specified functions.
821: The values of variables may be interrogated with the
822: .Ic display
823: command.
824: The variables which may be set or unset, but not toggled, are
1.22 aaron 825: listed here.
826: In addition, any of the variables for the
1.1 deraadt 827: .Ic toggle
828: command may be explicitly set or unset using
829: the
830: .Ic set
831: and
832: .Ic unset
833: commands.
834: .Bl -tag -width escape
835: .It Ic ayt
836: If
837: .Tn TELNET
1.12 aaron 838: is in
839: .Ic localchars
840: mode, or
1.1 deraadt 841: .Dv LINEMODE
842: is enabled, and the status character is typed, a
843: .Dv TELNET AYT
844: sequence (see
845: .Ic send ayt
846: preceding) is sent to the
1.22 aaron 847: remote host.
848: The initial value for the "Are You There"
1.1 deraadt 849: character is the terminal's status character.
850: .It Ic echo
1.12 aaron 851: This is the value (initially ``^E'') which, when in
852: ``line by line'' mode, toggles between doing local echoing
1.1 deraadt 853: of entered characters (for normal processing), and suppressing
854: echoing of entered characters (for entering, say, a password).
855: .It Ic eof
856: If
1.22 aaron 857: .Nm
1.1 deraadt 858: is operating in
859: .Dv LINEMODE
1.12 aaron 860: or ``old line by line'' mode, entering this character
1.1 deraadt 861: as the first character on a line will cause this character to be
862: sent to the remote system.
1.12 aaron 863: The initial value of the
864: .Ic eof
865: character is taken to be the terminal's
1.1 deraadt 866: .Ic eof
867: character.
868: .It Ic erase
869: If
1.22 aaron 870: .Nm
1.1 deraadt 871: is in
872: .Ic localchars
873: mode (see
874: .Ic toggle
875: .Ic localchars
876: below),
1.12 aaron 877: and if
1.22 aaron 878: .Nm
1.12 aaron 879: is operating in ``character at a time'' mode, then when this
1.1 deraadt 880: character is typed, a
881: .Dv TELNET EC
882: sequence (see
883: .Ic send
884: .Ic ec
885: above)
886: is sent to the remote system.
1.12 aaron 887: The initial value for the
888: .Ic erase
889: character is taken to be
1.1 deraadt 890: the terminal's
891: .Ic erase
892: character.
893: .It Ic escape
894: This is the
1.22 aaron 895: .Nm
1.12 aaron 896: escape character (initially ``^['') which causes entry
1.1 deraadt 897: into
1.22 aaron 898: .Nm
1.1 deraadt 899: command mode (when connected to a remote system).
900: .It Ic flushoutput
901: If
1.22 aaron 902: .Nm
1.1 deraadt 903: is in
904: .Ic localchars
905: mode (see
906: .Ic toggle
907: .Ic localchars
908: below)
909: and the
910: .Ic flushoutput
911: character is typed, a
912: .Dv TELNET AO
913: sequence (see
914: .Ic send
915: .Ic ao
916: above)
917: is sent to the remote host.
1.12 aaron 918: The initial value for the
919: .Ic flush
920: character is taken to be
1.1 deraadt 921: the terminal's
922: .Ic flush
923: character.
924: .It Ic forw1
925: .It Ic forw2
926: If
927: .Tn TELNET
928: is operating in
929: .Dv LINEMODE ,
930: these are the
931: characters that, when typed, cause partial lines to be
1.22 aaron 932: forwarded to the remote system.
933: The initial value for
1.1 deraadt 934: the forwarding characters are taken from the terminal's
935: eol and eol2 characters.
936: .It Ic interrupt
937: If
1.22 aaron 938: .Nm
1.1 deraadt 939: is in
940: .Ic localchars
941: mode (see
942: .Ic toggle
943: .Ic localchars
944: below)
945: and the
946: .Ic interrupt
947: character is typed, a
948: .Dv TELNET IP
949: sequence (see
950: .Ic send
951: .Ic ip
952: above)
953: is sent to the remote host.
1.12 aaron 954: The initial value for the
955: .Ic interrupt
956: character is taken to be
1.1 deraadt 957: the terminal's
958: .Ic intr
959: character.
960: .It Ic kill
961: If
1.22 aaron 962: .Nm
1.1 deraadt 963: is in
964: .Ic localchars
965: mode (see
966: .Ic toggle
967: .Ic localchars
968: below),
1.12 aaron 969: and if
1.22 aaron 970: .Nm
1.12 aaron 971: is operating in ``character at a time'' mode, then when this
1.1 deraadt 972: character is typed, a
973: .Dv TELNET EL
974: sequence (see
975: .Ic send
976: .Ic el
977: above)
978: is sent to the remote system.
1.12 aaron 979: The initial value for the
980: .Ic kill
981: character is taken to be
1.1 deraadt 982: the terminal's
983: .Ic kill
984: character.
985: .It Ic lnext
986: If
1.22 aaron 987: .Nm
1.1 deraadt 988: is operating in
989: .Dv LINEMODE
1.12 aaron 990: or ``old line by line'' mode, then this character is taken to
1.1 deraadt 991: be the terminal's
992: .Ic lnext
993: character.
1.12 aaron 994: The initial value for the
995: .Ic lnext
996: character is taken to be
1.1 deraadt 997: the terminal's
998: .Ic lnext
999: character.
1000: .It Ic quit
1001: If
1.22 aaron 1002: .Nm
1.1 deraadt 1003: is in
1004: .Ic localchars
1005: mode (see
1006: .Ic toggle
1007: .Ic localchars
1008: below)
1009: and the
1010: .Ic quit
1011: character is typed, a
1012: .Dv TELNET BRK
1013: sequence (see
1014: .Ic send
1015: .Ic brk
1016: above)
1017: is sent to the remote host.
1.12 aaron 1018: The initial value for the
1019: .Ic quit
1020: character is taken to be
1.1 deraadt 1021: the terminal's
1022: .Ic quit
1023: character.
1024: .It Ic reprint
1025: If
1.22 aaron 1026: .Nm
1.1 deraadt 1027: is operating in
1028: .Dv LINEMODE
1.31 deraadt 1029: or ``old line by line'' mode, then this character is taken to
1.1 deraadt 1030: be the terminal's
1031: .Ic reprint
1032: character.
1.12 aaron 1033: The initial value for the
1034: .Ic reprint
1035: character is taken to be
1.1 deraadt 1036: the terminal's
1037: .Ic reprint
1038: character.
1039: .It Ic rlogin
1040: This is the rlogin escape character.
1041: If set, the normal
1042: .Tn TELNET
1043: escape character is ignored unless it is
1044: preceded by this character at the beginning of a line.
1.12 aaron 1045: This character, at the beginning of a line, followed by
1046: a "." closes the connection; when followed by a ^Z it
1.5 deraadt 1047: suspends the
1.22 aaron 1048: .Nm
1049: command.
1050: The initial state is to
1.12 aaron 1051: disable the
1052: .Ic rlogin
1053: escape character.
1.1 deraadt 1054: .It Ic start
1055: If the
1056: .Dv TELNET TOGGLE-FLOW-CONTROL
1057: option has been enabled,
1058: then this character is taken to
1059: be the terminal's
1060: .Ic start
1061: character.
1.12 aaron 1062: The initial value for the
1063: .Ic start
1064: character is taken to be
1.1 deraadt 1065: the terminal's
1066: .Ic start
1067: character.
1068: .It Ic stop
1069: If the
1070: .Dv TELNET TOGGLE-FLOW-CONTROL
1071: option has been enabled,
1072: then this character is taken to
1073: be the terminal's
1074: .Ic stop
1075: character.
1.12 aaron 1076: The initial value for the
1077: .Ic stop
1078: character is taken to be
1.1 deraadt 1079: the terminal's
1080: .Ic stop
1081: character.
1082: .It Ic susp
1083: If
1.22 aaron 1084: .Nm
1.1 deraadt 1085: is in
1086: .Ic localchars
1087: mode, or
1088: .Dv LINEMODE
1089: is enabled, and the
1090: .Ic suspend
1091: character is typed, a
1092: .Dv TELNET SUSP
1093: sequence (see
1094: .Ic send
1095: .Ic susp
1096: above)
1097: is sent to the remote host.
1.12 aaron 1098: The initial value for the
1099: .Ic suspend
1100: character is taken to be
1.1 deraadt 1101: the terminal's
1102: .Ic suspend
1103: character.
1104: .It Ic tracefile
1105: This is the file to which the output, caused by
1106: .Ic netdata
1107: or
1108: .Ic option
1109: tracing being
1110: .Dv TRUE ,
1.22 aaron 1111: will be written.
1112: If it is set to
1.1 deraadt 1113: .Dq Fl ,
1114: then tracing information will be written to standard output (the default).
1115: .It Ic worderase
1116: If
1.22 aaron 1117: .Nm
1.1 deraadt 1118: is operating in
1119: .Dv LINEMODE
1.12 aaron 1120: or ``old line by line'' mode, then this character is taken to
1.1 deraadt 1121: be the terminal's
1122: .Ic worderase
1123: character.
1.12 aaron 1124: The initial value for the
1125: .Ic worderase
1126: character is taken to be
1.1 deraadt 1127: the terminal's
1128: .Ic worderase
1129: character.
1130: .It Ic \&?
1131: Displays the legal
1132: .Ic set
1133: .Pq Ic unset
1134: commands.
1135: .El
1.17 aaron 1136: .It Ic skey Ar sequence challenge
1137: The
1138: .Ic skey
1.23 aaron 1139: command computes a response to the S/Key challenge.
1140: See
1.17 aaron 1141: .Xr skey 1
1142: for more information on the S/Key system.
1.16 aaron 1143: .It Ic slc Ar state
1.1 deraadt 1144: The
1145: .Ic slc
1146: command (Set Local Characters) is used to set
1.4 deraadt 1147: or change the state of the special
1.16 aaron 1148: characters when the
1.1 deraadt 1149: .Dv TELNET LINEMODE
1150: option has
1.22 aaron 1151: been enabled.
1152: Special characters are characters that get mapped to
1.1 deraadt 1153: .Tn TELNET
1154: commands sequences (like
1155: .Ic ip
1156: or
1.22 aaron 1157: .Ic quit )
1.1 deraadt 1158: or line editing characters (like
1159: .Ic erase
1160: and
1.22 aaron 1161: .Ic kill ) .
1.1 deraadt 1162: By default, the local special characters are exported.
1163: .Bl -tag -width Fl
1164: .It Ic check
1165: Verify the current settings for the current special characters.
1166: The remote side is requested to send all the current special
1167: character settings, and if there are any discrepancies with
1168: the local side, the local side will switch to the remote value.
1169: .It Ic export
1.22 aaron 1170: Switch to the local defaults for the special characters.
1171: The local default characters are those of the local terminal at
1.1 deraadt 1172: the time when
1.22 aaron 1173: .Nm
1.1 deraadt 1174: was started.
1175: .It Ic import
1176: Switch to the remote defaults for the special characters.
1177: The remote default characters are those of the remote system
1.16 aaron 1178: at the time when the
1.1 deraadt 1179: .Tn TELNET
1180: connection was established.
1181: .It Ic \&?
1182: Prints out help information for the
1183: .Ic slc
1184: command.
1185: .El
1186: .It Ic status
1187: Show the current status of
1.12 aaron 1188: .Nm telnet .
1.1 deraadt 1189: This includes the peer one is connected to, as well
1190: as the current mode.
1.16 aaron 1191: .It Ic toggle Ar arguments Op Ar ...
1.1 deraadt 1192: Toggle (between
1193: .Dv TRUE
1194: and
1195: .Dv FALSE )
1196: various flags that control how
1.22 aaron 1197: .Nm
1.1 deraadt 1198: responds to events.
1199: These flags may be set explicitly to
1200: .Dv TRUE
1201: or
1202: .Dv FALSE
1203: using the
1204: .Ic set
1205: and
1206: .Ic unset
1207: commands listed above.
1208: More than one argument may be specified.
1209: The state of these flags may be interrogated with the
1210: .Ic display
1211: command.
1212: Valid arguments are:
1213: .Bl -tag -width Ar
1214: .It Ic authdebug
1215: Turns on debugging information for the authentication code.
1216: .It Ic autoflush
1217: If
1218: .Ic autoflush
1219: and
1220: .Ic localchars
1221: are both
1222: .Dv TRUE ,
1223: then when the
1.12 aaron 1224: .Ic ao
1.1 deraadt 1225: or
1226: .Ic quit
1227: characters are recognized (and transformed into
1228: .Tn TELNET
1229: sequences; see
1230: .Ic set
1231: above for details),
1.22 aaron 1232: .Nm
1.1 deraadt 1233: refuses to display any data on the user's terminal
1234: until the remote system acknowledges (via a
1235: .Dv TELNET TIMING MARK
1236: option)
1237: that it has processed those
1238: .Tn TELNET
1239: sequences.
1240: The initial value for this toggle is
1241: .Dv TRUE
1242: if the terminal user had not
1243: done an "stty noflsh", otherwise
1244: .Dv FALSE
1245: (see
1.22 aaron 1246: .Xr stty 1 ) .
1.1 deraadt 1247: .It Ic autodecrypt
1248: When the
1249: .Dv TELNET ENCRYPT
1250: option is negotiated, by
1251: default the actual encryption (decryption) of the data
1.22 aaron 1252: stream does not start automatically.
1253: The
1.12 aaron 1254: .Ic autoencrypt
1255: .Pq Ic autodecrypt
1256: command states that encryption of the
1.1 deraadt 1257: output (input) stream should be enabled as soon as
1258: possible.
1259: .Pp
1260: .It Ic autologin
1261: If the remote side supports the
1262: .Dv TELNET AUTHENTICATION
1263: option
1264: .Tn TELNET
1.22 aaron 1265: attempts to use it to perform automatic authentication.
1266: If the
1.1 deraadt 1267: .Dv AUTHENTICATION
1268: option is not supported, the user's login
1.31 deraadt 1269: name is propagated through the
1.1 deraadt 1270: .Dv TELNET ENVIRON
1271: option.
1272: This command is the same as specifying
1273: .Ar a
1274: option on the
1275: .Ic open
1276: command.
1277: .It Ic autosynch
1278: If
1279: .Ic autosynch
1280: and
1281: .Ic localchars
1282: are both
1283: .Dv TRUE ,
1284: then when either the
1285: .Ic intr
1286: or
1287: .Ic quit
1.12 aaron 1288: character is typed (see
1.1 deraadt 1289: .Ic set
1290: above for descriptions of the
1291: .Ic intr
1292: and
1293: .Ic quit
1294: characters), the resulting
1295: .Tn TELNET
1296: sequence sent is followed by the
1297: .Dv TELNET SYNCH
1298: sequence.
1299: This procedure
1.12 aaron 1300: .Em should
1.1 deraadt 1301: cause the remote system to begin throwing away all previously
1302: typed input until both of the
1303: .Tn TELNET
1304: sequences have been read and acted upon.
1305: The initial value of this toggle is
1306: .Dv FALSE .
1307: .It Ic binary
1308: Enable or disable the
1309: .Dv TELNET BINARY
1310: option on both input and output.
1311: .It Ic inbinary
1312: Enable or disable the
1313: .Dv TELNET BINARY
1314: option on input.
1315: .It Ic outbinary
1316: Enable or disable the
1317: .Dv TELNET BINARY
1318: option on output.
1319: .It Ic crlf
1320: If this is
1321: .Dv TRUE ,
1322: then carriage returns will be sent as
1323: .Li <CR><LF> .
1324: If this is
1325: .Dv FALSE ,
1.31 deraadt 1326: then carriage returns will be sent as
1.1 deraadt 1327: .Li <CR><NUL> .
1328: The initial value for this toggle is
1329: .Dv FALSE .
1330: .It Ic crmod
1331: Toggle carriage return mode.
1332: When this mode is enabled, most carriage return characters received from
1333: the remote host will be mapped into a carriage return followed by
1334: a line feed.
1335: This mode does not affect those characters typed by the user, only
1336: those received from the remote host.
1337: This mode is not very useful unless the remote host
1.12 aaron 1338: only sends carriage return, but never line feeds.
1.1 deraadt 1339: The initial value for this toggle is
1340: .Dv FALSE .
1341: .It Ic debug
1.25 aaron 1342: Toggles socket level debugging (useful only to the superuser).
1.1 deraadt 1343: The initial value for this toggle is
1344: .Dv FALSE .
1345: .It Ic encdebug
1346: Turns on debugging information for the encryption code.
1347: .It Ic localchars
1348: If this is
1349: .Dv TRUE ,
1350: then the
1.12 aaron 1351: .Ic flush ,
1.1 deraadt 1352: .Ic interrupt ,
1.12 aaron 1353: .Ic quit ,
1.1 deraadt 1354: .Ic erase ,
1355: and
1356: .Ic kill
1357: characters (see
1358: .Ic set
1359: above) are recognized locally, and transformed into (hopefully) appropriate
1360: .Tn TELNET
1361: control sequences
1362: (respectively
1.12 aaron 1363: .Ic ao ,
1.1 deraadt 1364: .Ic ip ,
1.12 aaron 1365: .Ic brk ,
1.1 deraadt 1366: .Ic ec ,
1367: and
1.22 aaron 1368: .Ic el ;
1.1 deraadt 1369: see
1370: .Ic send
1371: above).
1372: The initial value for this toggle is
1373: .Dv TRUE
1.12 aaron 1374: in ``old line by line'' mode,
1.1 deraadt 1375: and
1376: .Dv FALSE
1.12 aaron 1377: in ``character at a time'' mode.
1.1 deraadt 1378: When the
1379: .Dv LINEMODE
1380: option is enabled, the value of
1381: .Ic localchars
1382: is ignored, and assumed to always be
1383: .Dv TRUE .
1384: If
1385: .Dv LINEMODE
1386: has ever been enabled, then
1387: .Ic quit
1388: is sent as
1.12 aaron 1389: .Ic abort ,
1390: and
1391: .Ic eof
1.1 deraadt 1392: and
1.5 deraadt 1393: .Ic suspend
1.1 deraadt 1394: are sent as
1.12 aaron 1395: .Ic eof
1396: and
1.5 deraadt 1397: .Ic susp
1398: (see
1.1 deraadt 1399: .Ic send
1400: above).
1401: .It Ic netdata
1402: Toggles the display of all network data (in hexadecimal format).
1403: The initial value for this toggle is
1404: .Dv FALSE .
1405: .It Ic options
1406: Toggles the display of some internal
1.22 aaron 1407: .Nm
1.1 deraadt 1408: protocol processing (having to do with
1409: .Tn TELNET
1410: options).
1411: The initial value for this toggle is
1412: .Dv FALSE .
1413: .It Ic prettydump
1414: When the
1415: .Ic netdata
1416: toggle is enabled, if
1417: .Ic prettydump
1418: is enabled the output from the
1419: .Ic netdata
1420: command will be formatted in a more user readable format.
1421: Spaces are put between each character in the output, and the
1422: beginning of any
1423: .Tn TELNET
1424: escape sequence is preceded by a '*' to aid in locating them.
1425: .It Ic skiprc
1426: When the skiprc toggle is
1427: .Dv TRUE ,
1428: .Tn TELNET
1429: skips the reading of the
1430: .Pa \&.telnetrc
1.12 aaron 1431: file in the user's home
1.22 aaron 1432: directory when connections are opened.
1433: The initial value for this toggle is
1.13 aaron 1434: .Dv FALSE .
1.1 deraadt 1435: .It Ic termdata
1436: Toggles the display of all terminal data (in hexadecimal format).
1437: The initial value for this toggle is
1438: .Dv FALSE .
1439: .It Ic verbose_encrypt
1440: When the
1441: .Ic verbose_encrypt
1442: toggle is
1443: .Dv TRUE ,
1.22 aaron 1444: .Nm
1.1 deraadt 1445: prints out a message each time encryption is enabled or
1.22 aaron 1446: disabled.
1447: The initial value for this toggle is
1.13 aaron 1448: .Dv FALSE .
1.1 deraadt 1449: .It Ic \&?
1450: Displays the legal
1451: .Ic toggle
1452: commands.
1453: .El
1454: .It Ic z
1455: Suspend
1.12 aaron 1456: .Nm telnet .
1.1 deraadt 1457: This command only works when the user is using the
1.12 aaron 1458: .Xr csh 1 .
1.16 aaron 1459: .It Ic \&! Op Ar command
1.1 deraadt 1460: Execute a single command in a subshell on the local
1.22 aaron 1461: system.
1462: If
1.5 deraadt 1463: .Ar command
1.1 deraadt 1464: is omitted, then an interactive
1465: subshell is invoked.
1.16 aaron 1466: .It Ic \&? Op Ar command
1.22 aaron 1467: Get help.
1468: With no arguments,
1469: .Nm
1.1 deraadt 1470: prints a help summary.
1471: If a command is specified,
1.22 aaron 1472: .Nm
1.1 deraadt 1473: will print the help information for just that command.
1474: .El
1475: .Sh ENVIRONMENT
1.22 aaron 1476: .Nm
1.1 deraadt 1477: uses at least the
1478: .Ev HOME ,
1479: .Ev SHELL ,
1480: .Ev DISPLAY ,
1481: and
1482: .Ev TERM
1483: environment variables.
1484: Other environment variables may be propagated
1485: to the other side via the
1486: .Dv TELNET ENVIRON
1487: option.
1488: .Sh FILES
1489: .Bl -tag -width ~/.telnetrc -compact
1490: .It Pa ~/.telnetrc
1491: user customized telnet startup values
1492: .El
1493: .Sh HISTORY
1494: The
1.22 aaron 1495: .Nm
1.1 deraadt 1496: command appeared in
1497: .Bx 4.2 .
1498: .Sh NOTES
1499: On some remote systems, echo has to be turned off manually when in
1.12 aaron 1500: ``old line by line'' mode.
1.1 deraadt 1501: .Pp
1.16 aaron 1502: In ``old line by line'' mode or
1.1 deraadt 1503: .Dv LINEMODE
1504: the terminal's
1505: .Ic eof
1506: character is only recognized (and sent to the remote system)
1507: when it is the first character on a line.
1.20 itojun 1508: .Pp
1509: Source routing is not supported yet for IPv6.