{ "content": [ { "type": "text", "text": "# telnet (man)\n\n## NAME\n\ntelnet — user interface to the TELNET protocol\n\n## SYNOPSIS\n\ntelnet [options ...] [host [port]]\n\n## DESCRIPTION\n\nThe telnet command is used to communicate with another host using the TELNET protocol. If\ntelnet is invoked without the host argument, it enters command mode, indicated by its prompt\n(telnet>). In this mode, it accepts and executes the commands listed below. If it is in‐\nvoked with arguments, it performs an open command with those arguments.\n\n## TLDR\n\n> Connect to a specified port of a host using the telnet protocol.\n\n- Telnet to the default port of a host:\n `telnet {{host}}`\n- Telnet to a specific port of a host:\n `telnet {{ip_address}} {{port}}`\n- [Interactive] Exit a telnet session:\n `quit`\n- Emit the default escape character combination for terminating the session:\n ``\n- Start `telnet` with \"x\" as the session termination character:\n `telnet {{-e|--escape}} {{x}} {{ip_address}} {{port}}`\n- Telnet to Star Wars animation:\n `telnet {{towel.blinkenlights.nl}}`\n\n*Source: tldr-pages*\n\n## Sections\n\n- **NAME**\n- **SYNOPSIS**\n- **DESCRIPTION**\n- **OPTIONS** (16 subsections)\n- **OPERATION**\n- **ENVIRONMENT**\n- **FILES**\n- **HISTORY**\n- **NOTES**\n\nUse structuredContent.sections for detailed options, examples, and full documentation.\n" } ], "structuredContent": { "command": "telnet", "section": "", "mode": "man", "summary": "telnet — user interface to the TELNET protocol", "synopsis": "telnet [options ...] [host [port]]", "tldr_summary": "Connect to a specified port of a host using the telnet protocol.", "tldr_examples": [ { "description": "Telnet to the default port of a host", "command": "telnet {{host}}" }, { "description": "Telnet to a specific port of a host", "command": "telnet {{ip_address}} {{port}}" }, { "description": "[Interactive] Exit a telnet session", "command": "quit" }, { "description": "Emit the default escape character combination for terminating the session", "command": "" }, { "description": "Start `telnet` with \"x\" as the session termination character", "command": "telnet {{-e|--escape}} {{x}} {{ip_address}} {{port}}" }, { "description": "Telnet to Star Wars animation", "command": "telnet {{towel.blinkenlights.nl}}" } ], "tldr_source": "official", "flags": [ { "flag": "-4", "long": "--ipv4", "arg": null, "description": "Use IPv4 to connect to hosts." }, { "flag": "-6", "long": "--ipv6", "arg": null, "description": "Use IPv6 to connect to hosts." }, { "flag": "-8", "long": "--binary", "arg": null, "description": "Specifies an 8-bit data path. This causes an attempt to negotiate the TELNET BINARY option on both input and output." }, { "flag": "-L", "long": "--binary-output", "arg": null, "description": "Specifies an 8-bit data path on output. This causes the BINARY option to be negoti‐ ated on output." }, { "flag": "-e", "long": "--escape", "arg": null, "description": "Sets the initial telnet escape character to escape-char. If escape-char is omitted, then there will be no escape character." }, { "flag": "-E", "long": "--no-escape", "arg": null, "description": "Stops any character from being recognized as an escape character." }, { "flag": "-a", "long": "--login", "arg": null, "description": "Attempt automatic login. Currently, this sends the user name via the USER variable of the ENVIRON option if supported by the remote system. The name used is that of the current user as returned by getlogin(2) if it agrees with the current user ID, otherwise it is the name associated with the user ID." }, { "flag": "-K", "long": "--no-login", "arg": null, "description": "Specifies no automatic login to the remote system." }, { "flag": "-l", "long": "--user", "arg": null, "description": "When connecting to the remote system, if the remote system understands the ENVIRON option, then user will be sent to the remote system as the value for the variable USER. This option implies the -a option. This option may also be used with the open command." }, { "flag": "-n", "long": "--trace", "arg": null, "description": "Opens tracefile for recording trace information. See the set tracefile command be‐ low." }, { "flag": "-r", "long": "--rlogin", "arg": null, "description": "Specifies a user interface similar to rlogin(1). In this mode, the escape character is set to the tilde (~) character, unless modified by the -e option." }, { "flag": "-c", "long": "--no-rc", "arg": null, "description": "Disables the reading of the user's .telnetrc file. (See the toggle skiprc command on this man page.)" }, { "flag": "-d", "long": "--debug", "arg": null, "description": "Sets the initial value of the debug toggle to TRUE" }, { "flag": "-x", "long": "--encrypt", "arg": null, "description": "Turns on encryption of the data stream if possible." }, { "flag": "-X", "long": "--disable-auth", "arg": null, "description": "Disables the atype type of authentication." }, { "flag": "-k", "long": "--realm", "arg": null, "description": "If Kerberos authentication is being used, the -k option requests that telnet obtain tickets for the remote host in realm realm instead of the remote host's realm, as de‐ termined by krbrealmofhost(3). host Indicates the official name, an alias, or the Internet address of a remote host. port Indicates a port number (address of an application). If a number is not specified, the default telnet port is used." } ], "examples": [], "see_also": [], "section_outline": [ { "name": "NAME", "lines": 2, "subsections": [] }, { "name": "SYNOPSIS", "lines": 2, "subsections": [] }, { "name": "DESCRIPTION", "lines": 5, "subsections": [] }, { "name": "OPTIONS", "lines": 1, "subsections": [ { "name": "-4, --ipv4", "lines": 2, "flag": "-4", "long": "--ipv4" }, { "name": "-6, --ipv6", "lines": 2, "flag": "-6", "long": "--ipv6" }, { "name": "-8 --binary", "lines": 3, "flag": "-8", "long": "--binary" }, { "name": "-L --binary-output", "lines": 3, "flag": "-L", "long": "--binary-output" }, { "name": "-e --escape _", "lines": 3, "flag": "-e", "long": "--escape" }, { "name": "-E --no-escape", "lines": 2, "flag": "-E", "long": "--no-escape" }, { "name": "-a --login", "lines": 5, "flag": "-a", "long": "--login" }, { "name": "-K --no-login", "lines": 2, "flag": "-K", "long": "--no-login" }, { "name": "-l --user _", "lines": 5, "flag": "-l", "long": "--user" }, { "name": "-n --trace _", "lines": 3, "flag": "-n", "long": "--trace" }, { "name": "-r --rlogin", "lines": 3, "flag": "-r", "long": "--rlogin" }, { "name": "-c --no-rc", "lines": 3, "flag": "-c", "long": "--no-rc" }, { "name": "-d --debug", "lines": 2, "flag": "-d", "long": "--debug" }, { "name": "-x --encrypt", "lines": 2, "flag": "-x", "long": "--encrypt" }, { "name": "-X --disable-auth _", "lines": 2, "flag": "-X", "long": "--disable-auth" }, { "name": "-k --realm _", "lines": 9, "flag": "-k", "long": "--realm" } ] }, { "name": "OPERATION", "lines": 487, "subsections": [] }, { "name": "ENVIRONMENT", "lines": 3, "subsections": [] }, { "name": "FILES", "lines": 2, "subsections": [] }, { "name": "HISTORY", "lines": 2, "subsections": [] }, { "name": "NOTES", "lines": 6, "subsections": [] } ], "sections": { "NAME": { "content": "telnet — user interface to the TELNET protocol\n", "subsections": [] }, "SYNOPSIS": { "content": "telnet [options ...] [host [port]]\n", "subsections": [] }, "DESCRIPTION": { "content": "The telnet command is used to communicate with another host using the TELNET protocol. If\ntelnet is invoked without the host argument, it enters command mode, indicated by its prompt\n(telnet>). In this mode, it accepts and executes the commands listed below. If it is in‐\nvoked with arguments, it performs an open command with those arguments.\n", "subsections": [] }, "OPTIONS": { "content": "", "subsections": [ { "name": "-4, --ipv4", "content": "Use IPv4 to connect to hosts.\n", "flag": "-4", "long": "--ipv4" }, { "name": "-6, --ipv6", "content": "Use IPv6 to connect to hosts.\n", "flag": "-6", "long": "--ipv6" }, { "name": "-8 --binary", "content": "Specifies an 8-bit data path. This causes an attempt to negotiate the TELNET BINARY\noption on both input and output.\n", "flag": "-8", "long": "--binary" }, { "name": "-L --binary-output", "content": "Specifies an 8-bit data path on output. This causes the BINARY option to be negoti‐\nated on output.\n", "flag": "-L", "long": "--binary-output" }, { "name": "-e --escape _", "content": "Sets the initial telnet escape character to escape-char. If escape-char is omitted,\nthen there will be no escape character.\n", "flag": "-e", "long": "--escape" }, { "name": "-E --no-escape", "content": "Stops any character from being recognized as an escape character.\n", "flag": "-E", "long": "--no-escape" }, { "name": "-a --login", "content": "Attempt automatic login. Currently, this sends the user name via the USER variable\nof the ENVIRON option if supported by the remote system. The name used is that of\nthe current user as returned by getlogin(2) if it agrees with the current user ID,\notherwise it is the name associated with the user ID.\n", "flag": "-a", "long": "--login" }, { "name": "-K --no-login", "content": "Specifies no automatic login to the remote system.\n", "flag": "-K", "long": "--no-login" }, { "name": "-l --user _", "content": "When connecting to the remote system, if the remote system understands the ENVIRON\noption, then user will be sent to the remote system as the value for the variable\nUSER. This option implies the -a option. This option may also be used with the open\ncommand.\n", "flag": "-l", "long": "--user" }, { "name": "-n --trace _", "content": "Opens tracefile for recording trace information. See the set tracefile command be‐\nlow.\n", "flag": "-n", "long": "--trace" }, { "name": "-r --rlogin", "content": "Specifies a user interface similar to rlogin(1). In this mode, the escape character\nis set to the tilde (~) character, unless modified by the -e option.\n", "flag": "-r", "long": "--rlogin" }, { "name": "-c --no-rc", "content": "Disables the reading of the user's .telnetrc file. (See the toggle skiprc command on\nthis man page.)\n", "flag": "-c", "long": "--no-rc" }, { "name": "-d --debug", "content": "Sets the initial value of the debug toggle to TRUE\n", "flag": "-d", "long": "--debug" }, { "name": "-x --encrypt", "content": "Turns on encryption of the data stream if possible.\n", "flag": "-x", "long": "--encrypt" }, { "name": "-X --disable-auth _", "content": "Disables the atype type of authentication.\n", "flag": "-X", "long": "--disable-auth" }, { "name": "-k --realm _", "content": "If Kerberos authentication is being used, the -k option requests that telnet obtain\ntickets for the remote host in realm realm instead of the remote host's realm, as de‐\ntermined by krbrealmofhost(3).\n\nhost Indicates the official name, an alias, or the Internet address of a remote host.\n\nport Indicates a port number (address of an application). If a number is not specified,\nthe default telnet port is used.\n", "flag": "-k", "long": "--realm" } ] }, "OPERATION": { "content": "When in rlogin mode, a line of the form ~. disconnects from the remote host; ~ is the telnet\nescape character. Similarly, the line ~^Z suspends the telnet session. The line ~^] escapes\nto the normal telnet escape prompt.\n\nOnce a connection has been opened, telnet will attempt to enable the TELNET LINEMODE option.\nIf this fails, then telnet will revert to one of two input modes: either “character at a\ntime” or “old line by line” depending on what the remote system supports.\n\nWhen LINEMODE is enabled, character processing is done on the local system, under the control\nof the remote system. When input editing or character echoing is to be disabled, the remote\nsystem will relay that information. The remote system will also relay changes to any special\ncharacters that happen on the remote system, so that they can take effect on the local sys‐\ntem.\n\nIn “character at a time” mode, most text typed is immediately sent to the remote host for\nprocessing.\n\nIn “old line by line” mode, all text is echoed locally, and (normally) only completed lines\nare sent to the remote host. The “local echo character” (initially “^E”) may be used to turn\noff and on the local echo (this would mostly be used to enter passwords without the password\nbeing echoed).\n\nIf the LINEMODE option is enabled, or if the localchars toggle is TRUE (the default for “old\nline by line“; see below), the user's quit, intr, and flush characters are trapped locally,\nand sent as TELNET protocol sequences to the remote side. If LINEMODE has ever been enabled,\nthen the user's susp and eof are also sent as TELNET protocol sequences, and quit is sent as\na TELNET ABORT instead of BREAK There are options (see toggle autoflush and toggle autosynch\nbelow) which cause this action to flush subsequent output to the terminal (until the remote\nhost acknowledges the TELNET sequence) and flush previous terminal input (in the case of quit\nand intr).\n\nWhile connected to a remote host, telnet command mode may be entered by typing the telnet\n“escape character” (initially “^]”). When in command mode, the normal terminal editing con‐\nventions are available.\n\nThe following telnet commands are available. Only enough of each command to uniquely iden‐\ntify it need be typed (this is also true for arguments to the mode, set, toggle, unset, slc,\nenviron, and display commands).\n\nauth argument ...\nThe auth command manipulates the information sent through the TELNET AUTHENTICATE\noption. Valid arguments for the auth command are as follows:\n\ndisable type Disables the specified type of authentication. To obtain a list of\navailable types, use the auth disable ? command.\n\nenable type Enables the specified type of authentication. To obtain a list of\navailable types, use the auth enable ? command.\n\nstatus Lists the current status of the various types of authentication.\n\nclose Close a TELNET session and return to command mode.\n\ndisplay argument ...\nDisplays all, or some, of the set and toggle values (see below).\n\nencrypt argument ...\nThe encrypt command manipulates the information sent through the TELNET ENCRYPT\noption.\n\nNote: Because of export controls, the TELNET ENCRYPT option is not supported out‐\nside of the United States and Canada.\n\nValid arguments for the encrypt command are as follows:\n\ndisable type [input|output]\nDisables the specified type of encryption. If you omit the input\nand output, both input and output are disabled. To obtain a list of\navailable types, use the encrypt disable ? command.\n\nenable type [input|output]\nEnables the specified type of encryption. If you omit input and\noutput, both input and output are enabled. To obtain a list of\navailable types, use the encrypt enable ? command.\n\ninput This is the same as the encrypt start input command.\n\n-input This is the same as the encrypt stop input command.\n\noutput This is the same as the encrypt start output command.\n\n-output This is the same as the encrypt stop output command.\n\nstart [input|output]\nAttempts to start encryption. If you omit input and output, both\ninput and output are enabled. To obtain a list of available types,\nuse the encrypt enable ? command.\n\nstatus Lists the current status of encryption.\n\nstop [input|output]\nStops encryption. If you omit input and output, encryption is on\nboth input and output.\n\ntype type Sets the default type of encryption to be used with later encrypt\nstart or encrypt stop commands.\n\nenviron arguments...\nThe environ command is used to manipulate the the variables that my be sent\nthrough the TELNET ENVIRON option. The initial set of variables is taken from the\nusers environment, with only the DISPLAY and PRINTER variables being exported by\ndefault. The USER variable is also exported if the -a or -l options are used.\nValid arguments for the environ command are:\n\ndefine variable value\nDefine the variable variable to have a value of value. Any variables\ndefined by this command are automatically exported. The value may be\nenclosed in single or double quotes so that tabs and spaces may be in‐\ncluded.\n\nundefine variable\nRemove variable from the list of environment variables.\n\nexport variable\nMark the variable variable to be exported to the remote side.\n\nunexport variable\nMark the variable variable to not be exported unless explicitly asked\nfor by the remote side.\n\nlist List the current set of environment variables. Those marked with a *\nwill be sent automatically, other variables will only be sent if ex‐\nplicitly requested.\n\n? Prints out help information for the environ command.\n\nlogout Sends the TELNET LOGOUT option to the remote side. This command is similar to a\nclose command; however, if the remote side does not support the LOGOUT option,\nnothing happens. If, however, the remote side does support the LOGOUT option,\nthis command should cause the remote side to close the TELNET connection. If the\nremote side also supports the concept of suspending a user's session for later\nreattachment, the logout argument indicates that you should terminate the session\nimmediately.\n\nmode type Type is one of several options, depending on the state of the TELNET session. The\nremote host is asked for permission to go into the requested mode. If the remote\nhost is capable of entering that mode, the requested mode will be entered.\n\ncharacter Disable the TELNET LINEMODE option, or, if the remote side does not\nunderstand the LINEMODE option, then enter “character at a time“\nmode.\n\nline Enable the TELNET LINEMODE option, or, if the remote side does not\nunderstand the LINEMODE option, then attempt to enter “old-line-by-\nline“ mode.\n\nisig (-isig) Attempt to enable (disable) the TRAPSIG mode of the LINEMODE option.\nThis requires that the LINEMODE option be enabled.\n\nedit (-edit) Attempt to enable (disable) the EDIT mode of the LINEMODE option.\nThis requires that the LINEMODE option be enabled.\n\nsofttabs (-softtabs)\nAttempt to enable (disable) the SOFTTAB mode of the LINEMODE op‐\ntion. This requires that the LINEMODE option be enabled.\n\nlitecho (-litecho)\nAttempt to enable (disable) the LITECHO mode of the LINEMODE op‐\ntion. This requires that the LINEMODE option be enabled.\n\n? Prints out help information for the mode command.\n\nopen host [[-l] user][- port]\nOpen a connection to the named host. If no port number is specified, telnet will\nattempt to contact a TELNET server at the default port. The host specification\nmay be either a host name (see hosts(5)) or an Internet address specified in the\n“dot notation” (see inet(3)). The [-l] option may be used to specify the user\nname to be passed to the remote system via the ENVIRON option. When connecting to\na non-standard port, telnet omits any automatic initiation of TELNET options.\nWhen the port number is preceded by a minus sign, the initial option negotiation\nis done. After establishing a connection, the file .telnetrc in the users home\ndirectory is opened. Lines beginning with a # are comment lines. Blank lines are\nignored. Lines that begin without white space are the start of a machine entry.\nThe first thing on the line is the name of the machine that is being connected to.\nThe rest of the line, and successive lines that begin with white space are assumed\nto be telnet commands and are processed as if they had been typed in manually to\nthe telnet command prompt.\n\nquit Close any open TELNET session and exit telnet. An end of file (in command mode)\nwill also close a session and exit.\n\nsend arguments\nSends one or more special character sequences to the remote host. The following\nare the arguments which may be specified (more than one argument may be specified\nat a time):\n\nabort Sends the TELNET ABORT (Abort processes) sequence.\n\nao Sends the TELNET AO (Abort Output) sequence, which should cause the remote\nsystem to flush all output from the remote system to the user's terminal.\n\nayt Sends the TELNET AYT (Are You There) sequence, to which the remote system\nmay or may not choose to respond.\n\nbrk Sends the TELNET BRK (Break) sequence, which may have significance to the\nremote system.\n\nec Sends the TELNET EC (Erase Character) sequence, which should cause the re‐\nmote system to erase the last character entered.\n\nel Sends the TELNET EL (Erase Line) sequence, which should cause the remote\nsystem to erase the line currently being entered.\n\neof Sends the TELNET EOF (End Of File) sequence.\n\neor Sends the TELNET EOR (End of Record) sequence.\n\nescape Sends the current telnet escape character (initially “^”).\n\nga Sends the TELNET GA (Go Ahead) sequence, which likely has no significance\nto the remote system.\n\ngetstatus\nIf the remote side supports the TELNET STATUS command, getstatus will send\nthe subnegotiation to request that the server send its current option sta‐\ntus.\n\nip Sends the TELNET IP (Interrupt Process) sequence, which should cause the\nremote system to abort the currently running process.\n\nnop Sends the TELNET NOP (No OPeration) sequence.\n\nsusp Sends the TELNET SUSP (SUSPend process) sequence.\n\nsynch Sends the TELNET SYNCH sequence. This sequence causes the remote system\nto discard all previously typed (but not yet read) input. This sequence\nis sent as TCP urgent data (and may not work if the remote system is a\n4.2BSD system -- if it doesn't work, a lower case “r” may be echoed on the\nterminal).\n\ndo cmd\n\ndont cmd\n\nwill cmd\n\nwont cmd\nSends the TELNET DO cmd sequence. Cmd can be either a decimal number be‐\ntween 0 and 255, or a symbolic name for a specific TELNET command. Cmd\ncan also be either help or ? to print out help information, including a\nlist of known symbolic names.\n\n? Prints out help information for the send command.\n\nset argument value\n\nunset argument value\nThe set command will set any one of a number of telnet variables to a specific\nvalue or to TRUE. The special value off turns off the function associated with\nthe variable, this is equivalent to using the unset command. The unset command\nwill disable or set to FALSE any of the specified functions. The values of vari‐\nables may be interrogated with the display command. The variables which may be\nset or unset, but not toggled, are listed here. In addition, any of the variables\nfor the toggle command may be explicitly set or unset using the set and unset com‐\nmands.\n\nayt If TELNET is in localchars mode, or LINEMODE is enabled, and the status\ncharacter is typed, a TELNET AYT sequence (see send ayt preceding) is sent\nto the remote host. The initial value for the \"Are You There\" character\nis the terminal's status character.\n\necho This is the value (initially “^E”) which, when in “line by line” mode,\ntoggles between doing local echoing of entered characters (for normal pro‐\ncessing), and suppressing echoing of entered characters (for entering,\nsay, a password).\n\neof If telnet is operating in LINEMODE or “old line by line” mode, entering\nthis character as the first character on a line will cause this character\nto be sent to the remote system. The initial value of the eof character\nis taken to be the terminal's eof character.\n\nerase If telnet is in localchars mode (see toggle localchars below), and if\ntelnet is operating in “character at a time” mode, then when this charac‐\nter is typed, a TELNET EC sequence (see send ec above) is sent to the re‐\nmote system. The initial value for the erase character is taken to be the\nterminal's erase character.\n\nescape This is the telnet escape character (initially “^[”) which causes entry\ninto telnet command mode (when connected to a remote system).\n\nflushoutput\nIf telnet is in localchars mode (see toggle localchars below) and the\nflushoutput character is typed, a TELNET AO sequence (see send ao above)\nis sent to the remote host. The initial value for the flush character is\ntaken to be the terminal's flush character.\n\nforw1\n\nforw2 If TELNET is operating in LINEMODE, these are the characters that, when\ntyped, cause partial lines to be forwarded to the remote system. The ini‐\ntial value for the forwarding characters are taken from the terminal's eol\nand eol2 characters.\n\ninterrupt\nIf telnet is in localchars mode (see toggle localchars below) and the\ninterrupt character is typed, a TELNET IP sequence (see send ip above) is\nsent to the remote host. The initial value for the interrupt character is\ntaken to be the terminal's intr character.\n\nkill If telnet is in localchars mode (see toggle localchars below), and if\ntelnet is operating in “character at a time” mode, then when this charac‐\nter is typed, a TELNET EL sequence (see send el above) is sent to the re‐\nmote system. The initial value for the kill character is taken to be the\nterminal's kill character.\n\nlnext If telnet is operating in LINEMODE or “old line by line“ mode, then this\ncharacter is taken to be the terminal's lnext character. The initial\nvalue for the lnext character is taken to be the terminal's lnext charac‐\nter.\n\nquit If telnet is in localchars mode (see toggle localchars below) and the quit\ncharacter is typed, a TELNET BRK sequence (see send brk above) is sent to\nthe remote host. The initial value for the quit character is taken to be\nthe terminal's quit character.\n\nreprint\nIf telnet is operating in LINEMODE or “old line by line“ mode, then this\ncharacter is taken to be the terminal's reprint character. The initial\nvalue for the reprint character is taken to be the terminal's reprint\ncharacter.\n\nrlogin This is the rlogin escape character. If set, the normal TELNET escape\ncharacter is ignored unless it is preceded by this character at the begin‐\nning of a line. This character, at the beginning of a line followed by a\n\".\" closes the connection; when followed by a ^Z it suspends the telnet\ncommand. The initial state is to disable the rlogin escape character.\n\nstart If the TELNET TOGGLE-FLOW-CONTROL option has been enabled, then this char‐\nacter is taken to be the terminal's start character. The initial value\nfor the kill character is taken to be the terminal's start character.\n\nstop If the TELNET TOGGLE-FLOW-CONTROL option has been enabled, then this char‐\nacter is taken to be the terminal's stop character. The initial value for\nthe kill character is taken to be the terminal's stop character.\n\nsusp If telnet is in localchars mode, or LINEMODE is enabled, and the suspend\ncharacter is typed, a TELNET SUSP sequence (see send susp above) is sent\nto the remote host. The initial value for the suspend character is taken\nto be the terminal's suspend character.\n\ntracefile\nThis is the file to which the output, caused by netdata or option tracing\nbeing TRUE, will be written. If it is set to “-”, then tracing informa‐\ntion will be written to standard output (the default).\n\nworderase\nIf telnet is operating in LINEMODE or “old line by line“ mode, then this\ncharacter is taken to be the terminal's worderase character. The initial\nvalue for the worderase character is taken to be the terminal's worderase\ncharacter.\n\n? Displays the legal set (unset) commands.\n\nslc state The slc command (Set Local Characters) is used to set or change the state of the\nthe special characters when the TELNET LINEMODE option has been enabled. Special\ncharacters are characters that get mapped to TELNET commands sequences (like ip or\nquit) or line editing characters (like erase and kill). By default, the local\nspecial characters are exported.\n\ncheck Verify the current settings for the current special characters. The\nremote side is requested to send all the current special character\nsettings, and if there are any discrepancies with the local side, the\nlocal side will switch to the remote value.\n\nexport Switch to the local defaults for the special characters. The local\ndefault characters are those of the local terminal at the time when\ntelnet was started.\n\nimport Switch to the remote defaults for the special characters. The remote\ndefault characters are those of the remote system at the time when the\nTELNET connection was established.\n\n? Prints out help information for the slc command.\n\nstatus Show the current status of telnet. This includes the peer one is connected to, as\nwell as the current mode.\n\ntoggle arguments ...\nToggle (between TRUE and FALSE) various flags that control how telnet responds to\nevents. These flags may be set explicitly to TRUE or FALSE using the set and\nunset commands listed above. More than one argument may be specified. The state\nof these flags may be interrogated with the display command. Valid arguments are:\n\nauthdebug Turns on debugging information for the authentication code.\n\nautoflush If autoflush and localchars are both TRUE, then when the ao, or quit\ncharacters are recognized (and transformed into TELNET sequences;\nsee set above for details), telnet refuses to display any data on\nthe user's terminal until the remote system acknowledges (via a\nTELNET TIMING MARK option) that it has processed those TELNET se‐\nquences. The initial value for this toggle is TRUE if the terminal\nuser had not done an \"stty noflsh\", otherwise FALSE (see stty(1)).\n\nautodecrypt When the TELNET ENCRYPT option is negotiated, by default the actual\nencryption (decryption) of the data stream does not start automati‐\ncally. The autoencrypt (autodecrypt) command states that encryption\nof the output (input) stream should be enabled as soon as possible.\n\n\nNote: Because of export controls, the TELNET ENCRYPT option is not\nsupported outside the United States and Canada.\n\nautologin If the remote side supports the TELNET AUTHENTICATION option TELNET\nattempts to use it to perform automatic authentication. If the\nAUTHENTICATION option is not supported, the user's login name are\npropagated through the TELNET ENVIRON option. This command is the\nsame as specifying a option on the open command.\n\nautosynch If autosynch and localchars are both TRUE, then when either the intr\nor quit characters is typed (see set above for descriptions of the\nintr and quit characters), the resulting TELNET sequence sent is\nfollowed by the TELNET SYNCH sequence. This procedure should cause\nthe remote system to begin throwing away all previously typed input\nuntil both of the TELNET sequences have been read and acted upon.\nThe initial value of this toggle is FALSE.\n\nbinary Enable or disable the TELNET BINARY option on both input and output.\n\ninbinary Enable or disable the TELNET BINARY option on input.\n\noutbinary Enable or disable the TELNET BINARY option on output.\n\ncrlf If this is TRUE, then carriage returns will be sent as . If\nthis is FALSE, then carriage returns will be send as . The\ninitial value for this toggle is FALSE.\n\ncrmod Toggle carriage return mode. When this mode is enabled, most car‐\nriage return characters received from the remote host will be mapped\ninto a carriage return followed by a line feed. This mode does not\naffect those characters typed by the user, only those received from\nthe remote host. This mode is not very useful unless the remote\nhost only sends carriage return, but never line feed. The initial\nvalue for this toggle is FALSE.\n\ndebug Toggles socket level debugging (useful only to the super user). The\ninitial value for this toggle is FALSE.\n\nencdebug Turns on debugging information for the encryption code.\n\nlocalchars If this is TRUE, then the flush, interrupt, quit, erase, and kill\ncharacters (see set above) are recognized locally, and transformed\ninto (hopefully) appropriate TELNET control sequences (respectively\nao, ip, brk, ec, and el; see send above). The initial value for\nthis toggle is TRUE in “old line by line” mode, and FALSE in “char‐\nacter at a time” mode. When the LINEMODE option is enabled, the\nvalue of localchars is ignored, and assumed to always be TRUE. If\nLINEMODE has ever been enabled, then quit is sent as abort, and eof\nand suspend are sent as eof and susp, see send above).\n\nnetdata Toggles the display of all network data (in hexadecimal format).\nThe initial value for this toggle is FALSE.\n\noptions Toggles the display of some internal telnet protocol processing\n(having to do with TELNET options). The initial value for this tog‐\ngle is FALSE.\n\nprettydump When the netdata toggle is enabled, if prettydump is enabled the\noutput from the netdata command will be formatted in a more user\nreadable format. Spaces are put between each character in the out‐\nput, and the beginning of any TELNET escape sequence is preceded by\na '*' to aid in locating them.\n\nskiprc When the skiprc toggle is TRUE, TELNET skips the reading of the\n.telnetrc file in the users home directory when connections are\nopened. The initial value for this toggle is FALSE.\n\ntermdata Toggles the display of all terminal data (in hexadecimal format).\nThe initial value for this toggle is FALSE.\n\nverboseencrypt\nWhen the verboseencrypt toggle is TRUE, TELNET prints out a message\neach time encryption is enabled or disabled. The initial value for\nthis toggle is FALSE. Note: Because of export controls, data en‐\ncryption is not supported outside of the United States and Canada.\n\n? Displays the legal toggle commands.\n\nz Suspend telnet. This command only works when the user is using the csh(1).\n\n! [command]\nExecute a single command in a subshell on the local system. If command is omit‐\nted, then an interactive subshell is invoked.\n\n? [command]\nGet help. With no arguments, telnet prints a help summary. If a command is spec‐\nified, telnet will print the help information for just that command.\n", "subsections": [] }, "ENVIRONMENT": { "content": "telnet uses at least the HOME, SHELL, DISPLAY, and TERM environment variables. Other envi‐\nronment variables may be propagated to the other side via the TELNET ENVIRON option.\n", "subsections": [] }, "FILES": { "content": "~/.telnetrc user customized telnet startup values\n", "subsections": [] }, "HISTORY": { "content": "The telnet command appeared in 4.2BSD.\n", "subsections": [] }, "NOTES": { "content": "On some remote systems, echo has to be turned off manually when in “old line by line” mode.\n\nIn “old line by line” mode or LINEMODE the terminal's eof character is only recognized (and\nsent to the remote system) when it is the first character on a line.\n\nGNU Network Utilities February 9, 2019 TELNET(1)", "subsections": [] } } } }