-\versionid $Id: config.but,v 1.13 2001/11/25 17:32:39 simon Exp $
+\versionid $Id: config.but,v 1.47 2002/12/18 16:23:10 simon Exp $
\C{config} Configuring PuTTY
\S{config-hostname} The host name section
+\cfg{winhelp-topic}{session.hostname}
+
The top box on the Session panel, labelled \q{Specify your
connection by host name}, contains the details that need to be
filled in before PuTTY can open a session at all.
summary of the differences between SSH, Telnet and rlogin.)
\b The \q{Port} box lets you specify which port number on the server
-to connect to. If you select Telnet, Rlogin, or SSH, this box will be
-filled in automatically to the usual value, and you will only need to
-change it if you have an unusual server. If you select Raw mode, you
-will almost certainly need to fill in the \q{Port} box.
+to connect to. If you select Telnet, Rlogin, or SSH, this box will
+be filled in automatically to the usual value, and you will only
+need to change it if you have an unusual server. If you select Raw
+mode (see \k{using-rawprot}), you will almost certainly need to fill
+in the \q{Port} box.
\S{config-saving} Loading and storing saved sessions
+\cfg{winhelp-topic}{session.saved}
+
The next part of the Session configuration panel allows you to save
your preferred PuTTY options so they will appear automatically the
next time you start PuTTY. It also allows you to create \e{saved
\S{config-closeonexit} \q{Close Window on Exit}
+\cfg{winhelp-topic}{session.coe}
+
Finally in the Session panel, there is an option labelled \q{Close
Window on Exit}. This controls whether the PuTTY session window
disappears as soon as the session inside it terminates. If you are
\H{config-logging} The Logging panel
+\cfg{winhelp-topic}{logging.main}
+
The Logging configuration panel allows you to save log files of your
PuTTY sessions, for debugging, analysis or future reference.
else can replay the session later in slow motion and watch to see
what went wrong.
+\b \q{Log SSH packet data}. In this mode (which is only used by SSH
+connections), the SSH message packets sent over the encrypted
+connection are written to the log file. You might need this to debug
+a network-level problem, or more likely to send to the PuTTY authors
+as part of a bug report. \e{BE WARNED} that if you log in using a
+password, the password will appear in the log file, so be sure to
+edit it out before sending the log file to anyone else!
+
\S{config-logfilename} \q{Log file name}
+\cfg{winhelp-topic}{logging.filename}
+
In this edit box you enter the name of the file you want to log the
session to. The \q{Browse} button will let you look around your file
system to find the right place to put the file; or if you already
\S{config-logfileexists} \q{What to do if the log file already exists}
+\cfg{winhelp-topic}{logging.exists}
+
This control allows you to specify what PuTTY should do if it tries
to start writing to a log file and it finds the file already exists.
You might want to automatically destroy the existing log file and
\S{config-autowrap} \q{Auto wrap mode initially on}
+\cfg{winhelp-topic}{terminal.autowrap}
+
Auto wrap mode controls what happens when text printed in a PuTTY
window reaches the right-hand edge of the window.
Auto wrap mode can be turned on and off by control sequences sent by
the server. This configuration option only controls the \e{default}
state. If you modify this option in mid-session using \q{Change
-Settings}, you will need to reset the terminal \#{ FIXME } before
-the change takes effect.
+Settings}, you will need to reset the terminal (see
+\k{reset-terminal}) before the change takes effect.
\S{config-decom} \q{DEC Origin Mode initially on}
+\cfg{winhelp-topic}{terminal.decom}
+
DEC Origin Mode is a minor option which controls how PuTTY
interprets cursor-position control sequences sent by the server.
like the wrong part of the screen, you could try turning DEC Origin
Mode on to see whether that helps.
-DEC Origin Mode can be turned on and off by control sequences sent by
-the server. This configuration option only controls the \e{default}
-state. If you modify this option in mid-session using \q{Change
-Settings}, you will need to reset the terminal \#{ FIXME } before
-the change takes effect.
+DEC Origin Mode can be turned on and off by control sequences sent
+by the server. This configuration option only controls the
+\e{default} state. If you modify this option in mid-session using
+\q{Change Settings}, you will need to reset the terminal (see
+\k{reset-terminal}) before the change takes effect.
\S{config-crlf} \q{Implicit CR in every LF}
+\cfg{winhelp-topic}{terminal.lfhascr}
+
Most servers send two control characters, CR and LF, to start a new
line of the screen. The CR character makes the cursor return to the
left-hand side of the screen. The LF character makes the cursor move
\S{config-erase} \q{Use background colour to erase screen}
+\cfg{winhelp-topic}{terminal.bce}
+
Not all terminals agree on what colour to turn the screen when the
server sends a \q{clear screen} sequence. Some terminals believe the
screen should always be cleared to the \e{default} background
default background colour. With this option enabled, it is done in
the \e{current} background colour.
+Background-colour erase can be turned on and off by control
+sequences sent by the server. This configuration option only
+controls the \e{default} state. If you modify this option in
+mid-session using \q{Change Settings}, you will need to reset the
+terminal (see \k{reset-terminal}) before the change takes effect.
+
\S{config-blink} \q{Enable blinking text}
+\cfg{winhelp-topic}{terminal.blink}
+
The server can ask PuTTY to display text that blinks on and off.
This is very distracting, so PuTTY allows you to turn blinking text
off completely.
+When blinking text is disabled and the server attempts to make some
+text blink, PuTTY will instead display the text with a bolded
+background colour.
+
+Blinking text can be turned on and off by control sequences sent by
+the server. This configuration option only controls the \e{default}
+state. If you modify this option in mid-session using \q{Change
+Settings}, you will need to reset the terminal (see
+\k{reset-terminal}) before the change takes effect.
+
+\S{config-answerback} \q{Answerback to ^E}
+
+\cfg{winhelp-topic}{terminal.answerback}
+
+This option controls what PuTTY will send back to the server if the
+server sends it the ^E enquiry character. Normally it just sends
+the string \q{PuTTY}.
+
+If you accidentally write the contents of a binary file to your
+terminal, you will probably find that it contains more than one ^E
+character, and as a result your next command line will probably read
+\q{PuTTYPuTTYPuTTY...} as if you had typed the answerback string
+multiple times at the keyboard. If you set the answerback string to
+be empty, this problem should go away, but doing so might cause
+other problems.
+
+Note that this is \e{not} the feature of PuTTY which the server will
+typically use to determine your terminal type. That feature is the
+\q{Terminal-type string} in the Connection panel; see
+\k{config-termtype} for details.
+
+You can include control characters in the answerback string using
+\c{^C} notation. (Use \c{^~} to get a literal \c{^}.)
+
\S{config-localecho} \q{Local echo}
+\cfg{winhelp-topic}{terminal.localecho}
+
With local echo disabled, characters you type into the PuTTY window
are not echoed in the window \e{by PuTTY}. They are simply sent to
the server. (The \e{server} might choose to echo them back to you;
\S{config-localedit} \q{Local line editing}
+\cfg{winhelp-topic}{terminal.localedit}
+
Normally, every character you type into the PuTTY window is sent
immediately to the server the moment you type it.
local line editing to be turned on, or force it to be turned off,
instead of relying on the automatic detection.
-\H{config-bell} The Bell panel
-
-The Bell panel controls the terminal bell feature: the server's
-ability to cause PuTTY to beep at you.
-
-In the default configuration, when the server sends the character
-with ASCII code 7 (Control-G), PuTTY will play the Windows Default
-Beep sound. This is not always what you want the terminal bell
-feature to do; the Bell panel allows you to configure alternative
-actions.
+\S{config-printing} Remote-controlled printing
-\S{config-bellstyle} \q{Set the style of bell}
+\cfg{winhelp-topic}{terminal.printing}
-This control allows you to select various different actions to occur
-on a terminal bell:
+A lot of VT100-compatible terminals support printing under control
+of the remote server. PuTTY supports this feature as well, but it is
+turned off by default.
-\b Selecting \q{None} disables the bell completely. In this mode,
-the server can send as many Control-G characters as it likes and
-nothing at all will happen.
+To enable remote-controlled printing, choose a printer from the
+\q{Printer to send ANSI printer output to} drop-down list box. This
+should allow you to select from all the printers you have installed
+drivers for on your computer. Alternatively, you can type the
+network name of a networked printer (for example,
+\c{\\\\printserver\\printer1}) even if you haven't already
+installed a driver for it on your own machine.
-\b \q{Play Windows Default Sound} is the default setting. It causes
-the Windows \q{Default Beep} sound to be played. To change what this
-sound is, or to test it if nothing seems to be happening, use the
-Sound configurer in the Windows Control Panel.
+When the remote server attempts to print some data, PuTTY will send
+that data to the printer \e{raw} - without translating it,
+attempting to format it, or doing anything else to it. It is up to
+you to ensure your remote server knows what type of printer it is
+talking to.
-\b \q{Play a custom sound file} allows you to specify a particular
-sound file to be used by PuTTY alone, or even by a particular
-individual PuTTY session. This allows you to distinguish your PuTTY
-beeps from any other beeps on the system. If you select this option,
-you will also need to enter the name of your sound file in the edit
-control \q{Custom sound file to play as a bell}.
+Since PuTTY sends data to the printer raw, it cannot offer options
+such as portrait versus landscape, print quality, or paper tray
+selection. All these things would be done by your PC printer driver
+(which PuTTY bypasses); if you need them done, you will have to find
+a way to configure your remote server to do them.
-\b \q{Visual bell} is a silent alternative to a beeping computer. In
-this mode, when the server sends a Control-G, the whole PuTTY window
-will flash white for a fraction of a second.
-
-\S{config-belltaskbar} \q{Taskbar/caption indication on bell}
-
-This feature controls what happens to the PuTTY window's entry in
-the Windows Taskbar if a bell occurs while the window does not have
-the input focus.
-
-In the default state (\q{Disabled}) nothing unusual happens.
-
-If you select \q{Steady}, then when a bell occurs and the window is
-not in focus, the window's Taskbar entry and its title bar will
-change colour to let you know that PuTTY session is asking for your
-attention. The change of colour will persist until you select the
-window, so you can leave several PuTTY windows minimised in your
-terminal, go away from your keyboard, and be sure not to have missed
-any important beeps when you get back.
-
-\q{Flashing} is even more eye-catching: the Taskbar entry will
-continuously flash on and off until you select the window.
-
-\S{config-bellovl} \q{Control the bell overload behaviour}
-
-A common user error in a terminal session is to accidentally run the
-Unix command \c{cat} (or equivalent) on an inappropriate file type,
-such as an executable, image file, or ZIP file. This produces a huge
-stream of non-text characters sent to the terminal, which typically
-includes a lot of bell characters. As a result of this the terminal
-often doesn't stop beeping for ten minutes, and everybody else in
-the office gets annoyed.
-
-To try to avoid this behaviour, or any other cause of excessive
-beeping, PuTTY includes a bell overload management feature. In the
-default configuration, receiving more than five bell characters in a
-two-second period will cause the overload feature to activate. Once
-the overload feature is active, further bells will have no effect at
-all, so the rest of your binary file will be sent to the screen in
-silence. After a period of five seconds during which no further
-bells are received, the overload feature will turn itself off again
-and bells will be re-enabled.
-
-If you want this feature completely disabled, you can turn it off
-using the checkbox \q{Bell is temporarily disabled when over-used}.
-
-Alternatively, if you like the bell overload feature but don't agree
-with the settings, you can configure the details: how many bells
-constitute an overload, how short a time period they have to arrive
-in to do so, and how much silent time is required before the
-overload feature will deactivate itself.
+To disable remote printing again, choose \q{None (printing
+disabled)} from the printer selection list. This is the default
+state.
\H{config-keyboard} The Keyboard panel
\S{config-backspace} Changing the action of the Backspace key
+\cfg{winhelp-topic}{keyboard.backspace}
+
Some terminals believe that the Backspace key should send the same
thing to the server as Control-H (ASCII code 8). Other terminals
believe that the Backspace key should send ASCII code 127 (usually
\S{config-homeend} Changing the action of the Home and End keys
+\cfg{winhelp-topic}{keyboard.homeend}
+
The Unix terminal emulator \c{rxvt} disagrees with the rest of the
world about what character sequences should be sent to the server by
the Home and End keys.
\S{config-funkeys} Changing the action of the function keys and keypad
+\cfg{winhelp-topic}{keyboard.funkeys}
+
This option affects the function keys (F1 to F12) and the top row of
the numeric keypad.
\S{config-appcursor} Controlling Application Cursor Keys mode
+\cfg{winhelp-topic}{keyboard.appcursor}
+
Application Cursor Keys mode is a way for the server to change the
control sequences sent by the arrow keys. In normal mode, the arrow
keys send \c{ESC [A} through to \c{ESC [D}. In application mode,
Application Cursor Keys mode can be turned on and off by the server,
depending on the application. PuTTY allows you to configure the
-initial state, and also allows you to disable application mode
-completely.
+initial state.
+
+You can also disable application cursor keys mode completely, using
+the \q{Features} configuration panel; see
+\k{config-features-application}.
\S{config-appkeypad} Controlling Application Keypad mode
+\cfg{winhelp-topic}{keyboard.appkeypad}
+
Application Keypad mode is a way for the server to change the
behaviour of the numeric keypad.
Application keypad mode can be turned on and off by the server,
depending on the application. PuTTY allows you to configure the
-initial state, and also allows you to disable application mode
-completely.
+initial state.
+
+You can also disable application keypad mode completely, using the
+\q{Features} configuration panel; see
+\k{config-features-application}.
\S{config-nethack} Using NetHack keypad mode
+\cfg{winhelp-topic}{keyboard.nethack}
+
PuTTY has a special mode for playing NetHack. You can enable it by
selecting \q{NetHack} in the \q{Initial state of numeric keypad}
control.
\S{config-compose} Enabling a DEC-like Compose key
+\cfg{winhelp-topic}{keyboard.compose}
+
DEC terminals have a Compose key, which provides an easy-to-remember
way of typing accented characters. You press Compose and then type
two more characters. The two characters are \q{combined} to produce
easy to remember; for example, composing \q{e} and \q{`} produces
the \q{\u00e8{e-grave}} character.
-If you enable the \q{Application and AltGr act as Compose key}
-option, the Windows Application key and the AltGr key will both have
-this behaviour.
+If your keyboard has a Windows Application key, it acts as a Compose
+key in PuTTY. Alternatively, if you enable the \q{AltGr acts as
+Compose key} option, the AltGr key will become a Compose key.
\S{config-ctrlalt} \q{Control-Alt is different from AltGr}
+\cfg{winhelp-topic}{keyboard.ctrlalt}
+
Some old keyboards do not have an AltGr key, which can make it
difficult to type some characters. PuTTY can be configured to treat
the key combination Ctrl + Left Alt the same way as the AltGr key.
so you can use it to type extra graphic characters if your keyboard
has any.
+(However, Ctrl-Alt will never act as a Compose key, regardless of the
+setting of \q{AltGr acts as Compose key} described in
+\k{config-compose}.)
+
+\H{config-bell} The Bell panel
+
+The Bell panel controls the terminal bell feature: the server's
+ability to cause PuTTY to beep at you.
+
+In the default configuration, when the server sends the character
+with ASCII code 7 (Control-G), PuTTY will play the Windows Default
+Beep sound. This is not always what you want the terminal bell
+feature to do; the Bell panel allows you to configure alternative
+actions.
+
+\S{config-bellstyle} \q{Set the style of bell}
+
+\cfg{winhelp-topic}{bell.style}
+
+This control allows you to select various different actions to occur
+on a terminal bell:
+
+\b Selecting \q{None} disables the bell completely. In this mode,
+the server can send as many Control-G characters as it likes and
+nothing at all will happen.
+
+\b \q{Play Windows Default Sound} is the default setting. It causes
+the Windows \q{Default Beep} sound to be played. To change what this
+sound is, or to test it if nothing seems to be happening, use the
+Sound configurer in the Windows Control Panel.
+
+\b \q{Play a custom sound file} allows you to specify a particular
+sound file to be used by PuTTY alone, or even by a particular
+individual PuTTY session. This allows you to distinguish your PuTTY
+beeps from any other beeps on the system. If you select this option,
+you will also need to enter the name of your sound file in the edit
+control \q{Custom sound file to play as a bell}.
+
+\b \q{Visual bell} is a silent alternative to a beeping computer. In
+this mode, when the server sends a Control-G, the whole PuTTY window
+will flash white for a fraction of a second.
+
+\S{config-belltaskbar} \q{Taskbar/caption indication on bell}
+
+\cfg{winhelp-topic}{bell.taskbar}
+
+This feature controls what happens to the PuTTY window's entry in
+the Windows Taskbar if a bell occurs while the window does not have
+the input focus.
+
+In the default state (\q{Disabled}) nothing unusual happens.
+
+If you select \q{Steady}, then when a bell occurs and the window is
+not in focus, the window's Taskbar entry and its title bar will
+change colour to let you know that PuTTY session is asking for your
+attention. The change of colour will persist until you select the
+window, so you can leave several PuTTY windows minimised in your
+terminal, go away from your keyboard, and be sure not to have missed
+any important beeps when you get back.
+
+\q{Flashing} is even more eye-catching: the Taskbar entry will
+continuously flash on and off until you select the window.
+
+\S{config-bellovl} \q{Control the bell overload behaviour}
+
+\cfg{winhelp-topic}{bell.overload}
+
+A common user error in a terminal session is to accidentally run the
+Unix command \c{cat} (or equivalent) on an inappropriate file type,
+such as an executable, image file, or ZIP file. This produces a huge
+stream of non-text characters sent to the terminal, which typically
+includes a lot of bell characters. As a result of this the terminal
+often doesn't stop beeping for ten minutes, and everybody else in
+the office gets annoyed.
+
+To try to avoid this behaviour, or any other cause of excessive
+beeping, PuTTY includes a bell overload management feature. In the
+default configuration, receiving more than five bell characters in a
+two-second period will cause the overload feature to activate. Once
+the overload feature is active, further bells will have no effect at
+all, so the rest of your binary file will be sent to the screen in
+silence. After a period of five seconds during which no further
+bells are received, the overload feature will turn itself off again
+and bells will be re-enabled.
+
+If you want this feature completely disabled, you can turn it off
+using the checkbox \q{Bell is temporarily disabled when over-used}.
+
+Alternatively, if you like the bell overload feature but don't agree
+with the settings, you can configure the details: how many bells
+constitute an overload, how short a time period they have to arrive
+in to do so, and how much silent time is required before the
+overload feature will deactivate itself.
+
+Bell overload mode is always deactivated by any keypress in the
+terminal. This means it can respond to large unexpected streams of
+data, but does not interfere with ordinary command-line activities
+that generate beeps (such as filename completion).
+
+\H{config-features} The Features panel
+
+PuTTY's terminal emulation is very highly featured, and can do a lot
+of things under remote server control. Some of these features can
+cause problems due to buggy or strangely configured server
+applications.
+
+The Features configuration panel allows you to disable some of
+PuTTY's more advanced terminal features, in case they cause trouble.
+
+\S{config-features-application} Disabling application keypad and cursor keys
+
+\cfg{winhelp-topic}{features.application}
+
+Application keypad mode (see \k{config-appkeypad}) and application
+cursor keys mode (see \k{config-appcursor}) alter the behaviour of
+the keypad and cursor keys. Some applications enable these modes but
+then do not deal correctly with the modified keys. You can force
+these modes to be permanently disabled no matter what the server
+tries to do.
+
+\S{config-features-mouse} Disabling \cw{xterm}-style mouse reporting
+
+\cfg{winhelp-topic}{features.mouse}
+
+PuTTY allows the server to send control codes that let it take over
+the mouse and use it for purposes other than copy and paste.
+Applications which use this feature include the text-mode web
+browser \c{links}, the Usenet newsreader \c{trn} version 4, and the
+file manager \c{mc} (Midnight Commander).
+
+If you find this feature inconvenient, you can disable it using the
+\q{Disable xterm-style mouse reporting} control. With this box
+ticked, the mouse will \e{always} do copy and paste in the normal
+way.
+
+Note that even if the application takes over the mouse, you can
+still manage PuTTY's copy and paste by holding down the Shift key
+while you select and paste, unless you have deliberately turned this
+feature off (see \k{config-mouseshift}).
+
+\S{config-features-resize} Disabling remote terminal resizing
+
+\cfg{winhelp-topic}{features.resize}
+
+PuTTY has the ability to change the terminal's size and position in
+response to commands from the server. If you find PuTTY is doing
+this unexpectedly or inconveniently, you can tell PuTTY not to
+respond to those server commands.
+
+\S{config-features-altscreen} Disabling switching to the alternate screen
+
+\cfg{winhelp-topic}{features.altscreen}
+
+Many terminals, including PuTTY, support an \q{alternate screen}.
+This is the same size as the ordinary terminal screen, but separate.
+Typically a screen-based program such as a text editor might switch
+the terminal to the alternate screen before starting up. Then at the
+end of the run, it switches back to the primary screen, and you see
+the screen contents just as they were before starting the editor.
+
+Some people prefer this not to happen. If you want your editor to
+run in the same screen as the rest of your terminal activity, you
+can disable the alternate screen feature completely.
+
+\S{config-features-retitle} Disabling remote window title changing
+
+\cfg{winhelp-topic}{features.retitle}
+
+PuTTY has the ability to change the window title in response to
+commands from the server. If you find PuTTY is doing this
+unexpectedly or inconveniently, you can tell PuTTY not to respond to
+those server commands.
+
+\S{config-features-dbackspace} Disabling destructive backspace
+
+\cfg{winhelp-topic}{features.dbackspace}
+
+Normally, when PuTTY receives character 127 (^?) from the server, it
+will perform a \q{destructive backspace}: move the cursor one space
+left and delete the character under it. This can apparently cause
+problems in some applications, so PuTTY provides the ability to
+configure character 127 to perform a normal backspace (without
+deleting a character) instead.
+
+\S{config-features-charset} Disabling remote character set
+configuration
+
+\cfg{winhelp-topic}{features.charset}
+
+PuTTY has the ability to change its character set configuration in
+response to commands from the server. Some programs send these
+commands unexpectedly or inconveniently. In particular, BitchX (an
+IRC client) seems to have a habit of reconfiguring the character set
+to something other than the user intended.
+
+If you find that accented characters are not showing up the way you
+expect them to, particularly if you're running BitchX, you could try
+disabling the remote character set configuration commands.
+
\H{config-window} The Window panel
The Window configuration panel allows you to control aspects of the
-PuTTY window and its behaviour.
+PuTTY window.
\S{config-winsize} Setting the size of the PuTTY window
+\cfg{winhelp-topic}{window.size}
+
The \q{Rows} and \q{Columns} boxes let you set the PuTTY window to a
precise size. Of course you can also drag the window to a new size
while a session is running.
-\S{config-winsizelock} Locking the size of the PuTTY window
+\S{config-winsizelock} What to do when the window is resized
+
+\cfg{winhelp-topic}{window.resize}
These options allow you to control what happens when the user tries
to resize the PuTTY window.
-When you resize the PuTTY window, one of three things can happen:
+When you resize the PuTTY window, one of four things can happen:
\b Nothing (if you have completely disabled resizes).
\b The number of rows and columns in the terminal can stay the same,
and the font size can change.
+\b You can allow PuTTY to change \e{either} the terminal size or the
+font size. In this mode it will change the terminal size most of the
+time, but enlarge the font when you maximise the window.
+
You can control which of these happens using the \q{Lock terminal
size against resizing} and \q{Lock font size against resizing}
options. If you lock both, the window will refuse to be resized at
\S{config-scrollback} Controlling scrollback
-Text that scrolls off the top of the PuTTY terminal window is kept
-for reference. The scrollbar on the right of the window lets you
-view the scrolled-off text. You can also page through the scrollback
-using the keyboard, by pressing Shift-PgUp and Shift-PgDn.
+\cfg{winhelp-topic}{window.scrollback}
+
+These options let you configure the way PuTTY keeps text after it
+scrolls off the top of the screen (see \k{using-scrollback}).
The \q{Lines of scrollback} box lets you configure how many lines of
-text PuTTY keeps. The \q{Display scrollbar} option allows you to
+text PuTTY keeps. The \q{Display scrollbar} options allow you to
hide the scrollbar (although you can still view the scrollback using
-Shift-PgUp and Shift-PgDn).
+Shift-PgUp and Shift-PgDn). You can separately configure whether the
+scrollbar is shown in full-screen mode and in normal modes.
If you are viewing part of the scrollback when the server sends more
text to PuTTY, the screen will revert to showing the current
screen revert when you press a key, by turning on \q{Reset
scrollback on keypress}.
-\S{config-warnonclose} \q{Warn before closing window}
-
-If you press the Close button in a PuTTY window that contains a
-running session, PuTTY will put up a warning window asking if you
-really meant to close the window. A window whose session has already
-terminated can always be closed without a warning.
-
-If you want to be able to close a window quickly, you can disable
-the \q{Warn before closing window} option.
-
-\S{config-altf4} \q{Window closes on ALT-F4}
-
-By default, pressing ALT-F4 causes the window to close (or a warning
-box to appear; see \k{config-warnonclose}). If you disable the
-\q{Window closes on ALT-F4} option, then pressing ALT-F4 will simply
-send a key sequence to the server.
-
-\S{config-altspace} \q{System menu appears on ALT-Space}
-
-If this option is enabled, then pressing ALT-Space will bring up the
-PuTTY window's menu, like clicking on the top left corner. If it is
-disabled, then pressing ALT-Space will just send \c{ESC SPACE} to
-the server.
-
-Some accessibility programs for Windows may need this option
-enabling to be able to control PuTTY's window successfully. For
-instance, Dragon NaturallySpeaking requires it both to open the
-system menu via voice, and to close, minimise, maximise and restore
-the window.
-
-\S{config-altonly} \q{System menu appears on Alt alone}
-
-If this option is enabled, then pressing and releasing ALT will
-bring up the PuTTY window's menu, like clicking on the top left
-corner. If it is disabled, then pressing and releasing ALT will have
-no effect.
-
-\S{config-alwaysontop} \q{Ensure window is always on top}
-
-If this option is enabled, the PuTTY window will stay on top of all
-other windows.
-
-\S{config-fullscreen} \q{Full screen on Alt-Enter}
-
-If this option is enabled, then pressing Alt-Enter will cause the
-PuTTY window to become full-screen - that is, it will not only
-maximise itself, it will expand so that the title bar goes off the
-top of the screen, and place itself on top of the Windows taskbar,
-so that \e{nothing} is visible on the screen except PuTTY. Pressing
-Alt-Enter again will restore the previous window size.
-
\H{config-appearance} The Appearance panel
The Appearance configuration panel allows you to control aspects of
-PuTTY's appearance.
+the appearance of PuTTY's window.
\S{config-cursor} Controlling the appearance of the cursor
+\cfg{winhelp-topic}{appearance.cursor}
+
The \q{Cursor appearance} option lets you configure the cursor to be
a block, an underline, or a vertical line. A block cursor becomes an
empty box when the window loses focus; an underline or a vertical
\S{config-font} Controlling the font used in the terminal window
+\cfg{winhelp-topic}{appearance.font}
+
This option allows you to choose what font, in what size, the PuTTY
terminal window uses to display the text in the session. You will be
offered a choice from all the fixed-width fonts installed on the
\S{config-title} Controlling the window title
+\cfg{winhelp-topic}{appearance.title}
+
The \q{Window title} edit box allows you to set the title of the
PuTTY window. By default the window title will contain the host name
followed by \q{PuTTY}, for example \c{server1.example.com - PuTTY}.
\S{config-mouseptr} \q{Hide mouse pointer when typing in window}
+\cfg{winhelp-topic}{appearance.hidemouse}
+
If you enable this option, the mouse pointer will disappear if the
PuTTY window is selected and you press a key. This way, it will not
obscure any of the text in the window while you work in your
\S{config-winborder} Controlling the window border
+\cfg{winhelp-topic}{appearance.border}
+
PuTTY allows you to configure the appearance of the window border to
some extent.
edge} control. By default this is set at one pixel. You can reduce
it to zero, or increase it further.
+\H{config-behaviour} The Behaviour panel
+
+The Behaviour configuration panel allows you to control aspects of
+the behaviour of PuTTY's window.
+
+\S{config-warnonclose} \q{Warn before closing window}
+
+\cfg{winhelp-topic}{behaviour.closewarn}
+
+If you press the Close button in a PuTTY window that contains a
+running session, PuTTY will put up a warning window asking if you
+really meant to close the window. A window whose session has already
+terminated can always be closed without a warning.
+
+If you want to be able to close a window quickly, you can disable
+the \q{Warn before closing window} option.
+
+\S{config-altf4} \q{Window closes on ALT-F4}
+
+\cfg{winhelp-topic}{behaviour.altf4}
+
+By default, pressing ALT-F4 causes the window to close (or a warning
+box to appear; see \k{config-warnonclose}). If you disable the
+\q{Window closes on ALT-F4} option, then pressing ALT-F4 will simply
+send a key sequence to the server.
+
+\S{config-altspace} \q{System menu appears on ALT-Space}
+
+\cfg{winhelp-topic}{behaviour.altspace}
+
+If this option is enabled, then pressing ALT-Space will bring up the
+PuTTY window's menu, like clicking on the top left corner. If it is
+disabled, then pressing ALT-Space will just send \c{ESC SPACE} to
+the server.
+
+Some accessibility programs for Windows may need this option
+enabling to be able to control PuTTY's window successfully. For
+instance, Dragon NaturallySpeaking requires it both to open the
+system menu via voice, and to close, minimise, maximise and restore
+the window.
+
+\S{config-altonly} \q{System menu appears on Alt alone}
+
+\cfg{winhelp-topic}{behaviour.altonly}
+
+If this option is enabled, then pressing and releasing ALT will
+bring up the PuTTY window's menu, like clicking on the top left
+corner. If it is disabled, then pressing and releasing ALT will have
+no effect.
+
+\S{config-alwaysontop} \q{Ensure window is always on top}
+
+\cfg{winhelp-topic}{behaviour.alwaysontop}
+
+If this option is enabled, the PuTTY window will stay on top of all
+other windows.
+
+\S{config-fullscreen} \q{Full screen on Alt-Enter}
+
+\cfg{winhelp-topic}{behaviour.altenter}
+
+If this option is enabled, then pressing Alt-Enter will cause the
+PuTTY window to become full-screen. Pressing Alt-Enter again will
+restore the previous window size.
+
+The full-screen feature is also available from the System menu, even
+when it is configured not to be available on the Alt-Enter key. See
+\k{using-fullscreen}.
+
\H{config-translation} The Translation panel
The Translation configuration panel allows you to control the
\S{config-charset} Controlling character set translation
+\cfg{winhelp-topic}{translation.codepage}
+
During an interactive session, PuTTY receives a stream of 8-bit
bytes from the server, and in order to display them on the screen it
needs to know what character set to interpret them in.
If you select \q{UTF-8} as a character set you can use this mode.
Not all server-side applications will support it.
+If you need support for a numeric code page which is not listed in
+the drop-down list, such as code page 866, then you should be able
+to enter its name manually (\c{CP866} for example) in the list box
+and get the right result.
+
\S{config-cyr} \q{Caps Lock acts as Cyrillic switch}
+\cfg{winhelp-topic}{translation.cyrillic}
+
This feature allows you to switch between a US/UK keyboard layout
and a Cyrillic keyboard layout by using the Caps Lock key, if you
need to type (for example) Russian and English side by side in the
\S{config-linedraw} Controlling display of line drawing characters
+\cfg{winhelp-topic}{translation.linedraw}
+
VT100-series terminals allow the server to send control sequences
that shift temporarily into a separate character set for drawing
lines and boxes. PuTTY has a variety of ways to support this
\S{config-linedrawpaste} Controlling the pasting of line drawing
characters
+\cfg{winhelp-topic}{selection.linedraw}
+
By default, when you copy and paste a piece of the PuTTY screen that
contains VT100 line and box drawing characters, PuTTY will translate
them into the \q{poor man's} line-drawing characters \c{+}, \c{-}
trying to recreate the same box layout in another program, for
example.
+\S{config-rtfpaste} Pasting in Rich Text Format
+
+\cfg{winhelp-topic}{selection.rtf}
+
+If you enable \q{Paste to clipboard in RTF as well as plain text},
+PuTTY will write formatting information to the clipboard as well as
+the actual text you copy. Currently the only effect of this will be
+that if you paste into (say) a word processor, the text will appear
+in the word processor in the same font PuTTY was using to display
+it. In future it is likely that other formatting information (bold,
+underline, colours) will be copied as well.
+
+This option can easily be inconvenient, so by default it is
+disabled.
+
\S{config-mouse} Changing the actions of the mouse buttons
+\cfg{winhelp-topic}{selection.buttons}
+
PuTTY's copy and paste mechanism is modelled on the Unix \c{xterm}
application. The X Window System uses a three-button mouse, and the
convention is that the left button selects, the right button extends
\S{config-mouseshift} \q{Shift overrides application's use of mouse}
+\cfg{winhelp-topic}{selection.shiftdrag}
+
PuTTY allows the server to send control codes that let it take over
the mouse and use it for purposes other than copy and paste.
Applications which use this feature include the text-mode web
checkbox will cause Shift + mouse clicks to go to the server as well
(so that mouse-driven copy and paste will be completely disabled).
+If you want to prevent the application from taking over the mouse at
+all, you can do this using the Features control panel; see
+\k{config-features-mouse}.
+
+\S{config-rectselect} Default selection mode
+
+\cfg{winhelp-topic}{selection.rect}
+
+As described in \k{using-selection}, PuTTY has two modes of
+selecting text to be copied to the clipboard. In the default mode
+(\q{Normal}), dragging the mouse from point A to point B selects to
+the end of the line containing A, all the lines in between, and from
+the very beginning of the line containing B. In the other mode
+(\q{Rectangular block}), dragging the mouse between two points
+defines a rectangle, and everything within that rectangle is copied.
+
+Normally, you have to hold down Alt while dragging the mouse to
+select a rectangular block. Using the \q{Default selection mode}
+control, you can set rectangular selection as the default, and then
+you have to hold down Alt to get the \e{normal} behaviour.
+
\S{config-charclasses} Configuring word-by-word selection
+\cfg{winhelp-topic}{selection.charclasses}
+
PuTTY will select a word at a time in the terminal window if you
double-click to begin the drag. This panel allows you to control
precisely what is considered to be a word.
This mechanism currently only covers ASCII characters, because it
isn't feasible to expand the list to cover the whole of Unicode.
+Character class definitions can be modified by control sequences
+sent by the server. This configuration option only controls the
+\e{default} state. If you modify this option in mid-session using
+\q{Change Settings}, you will need to reset the terminal (see
+\k{reset-terminal}) before the change takes effect.
+
\H{config-colours} The Colours panel
The Colours panel allows you to control PuTTY's use of colour.
\S{config-boldcolour} \q{Bolded text is a different colour}
+\cfg{winhelp-topic}{colours.bold}
+
When the server sends a control sequence indicating that some text
should be displayed in bold, PuTTY can handle this two ways. It can
either change the font for a bold version, or use the same font in a
\S{config-logpalette} \q{Attempt to use logical palettes}
+\cfg{winhelp-topic}{colours.logpal}
+
Logical palettes are a mechanism by which a Windows application
running on an 8-bit colour display can select precisely the colours
it wants instead of going with the Windows standard defaults.
\S{config-colourcfg} Adjusting the colours in the terminal window
+\cfg{winhelp-topic}{colours.config}
+
The main colour control allows you to specify exactly what colours
things should be displayed in. To modify one of the PuTTY colours,
use the list box to select which colour you want to modify. The RGB
\S{config-termtype} \q{Terminal-type string}
+\cfg{winhelp-topic}{connection.termtype}
+
Most servers you might connect to with PuTTY are designed to be
connected to from lots of different types of terminal. In order to
send the right control sequences to each one, the server will need
\S{config-username} \q{Auto-login username}
+\cfg{winhelp-topic}{connection.username}
+
All three of the SSH, Telnet and Rlogin protocols allow you to
specify what user name you want to log in as, without having to type
it explicitly every time. (Some Telnet servers don't support this.)
\S{config-keepalive} Using keepalives to prevent disconnection
+\cfg{winhelp-topic}{connection.keepalive}
+
If you find your sessions are closing unexpectedly (\q{Connection
reset by peer}) after they have been idle for a while, you might
want to try using this option.
Keepalives are only supported in Telnet and SSH; the Rlogin and Raw
protocols offer no way of implementing them.
+Note that if you are using SSH1 and the server has a bug that makes
+it unable to deal with SSH1 ignore messages (see
+\k{config-ssh-bug-ignore1}), enabling keepalives will have no effect.
+
+\S{config-nodelay} \q{Disable Nagle's algorithm}
+
+\cfg{winhelp-topic}{connection.nodelay}
+
+Nagle's algorithm is a detail of TCP/IP implementations that tries
+to minimise the number of small data packets sent down a network
+connection. With Nagle's algorithm enabled, PuTTY's bandwidth usage
+will be slightly more efficient; with it disabled, you may find you
+get a faster response to your keystrokes when connecting to some
+types of server.
+
+The Nagle algorithm is disabled by default.
+
+\H{config-proxy} The Proxy panel
+
+\cfg{winhelp-topic}{proxy.main}
+
+The Proxy panel allows you to configure PuTTY to use various types
+of proxy in order to make its network connections. The settings in
+this panel affect the primary network connection forming your PuTTY
+session, but also any extra connections made as a result of SSH port
+forwarding (see \k{using-port-forwarding}).
+
+\S{config-proxy-type} Setting the proxy type
+
+\cfg{winhelp-topic}{proxy.type}
+
+The \q{Proxy type} radio buttons allow you to configure what type of
+proxy you want PuTTY to use for its network connections. The default
+setting is \q{None}; in this mode no proxy is used for any
+connection.
+
+\b Selecting \q{HTTP} allows you to proxy your connections through a
+web server supporting the HTTP \cw{CONNECT} command, as documented
+in \W{http://www.ietf.org/rfc/rfc2817.txt}{RFC 2817}.
+
+\b Selecting \q{SOCKS} allows you to proxy your connections through
+a SOCKS server.
+
+\b Many firewalls implement a less formal type of proxy in which a
+user can make a Telnet connection directly to the firewall machine
+and enter a command such as \c{connect myhost.com 22} to connect
+through to an external host. Selecting \q{Telnet} allows you to tell
+PuTTY to use this type of proxy.
+
+\S{config-proxy-exclude} Excluding parts of the network from proxying
+
+\cfg{winhelp-topic}{proxy.exclude}
+
+Typically you will only need to use a proxy to connect to non-local
+parts of your network; for example, your proxy might be required for
+connections outside your company's internal network. In the
+\q{Exclude Hosts/IPs} box you can enter ranges of IP addresses, or
+ranges of DNS names, for which PuTTY will avoid using the proxy and
+make a direct connection instead.
+
+The \q{Exclude Hosts/IPs} box may contain more than one exclusion
+range, separated by commas. Each range can be an IP address or a DNS
+name, with a \c{*} character allowing wildcards. For example:
+
+\c *.example.com
+
+This excludes any host with a name ending in \c{.example.com} from
+proxying.
+
+\c 192.168.88.*
+
+This excludes any host with an IP address starting with 192.168.88
+from proxying.
+
+\c 192.168.88.*,*.example.com
+
+This excludes both of the above ranges at once.
+
+Connections to the local host (the host name \c{localhost}, and any
+loopback IP address) are never proxied, even if the proxy exclude
+list does not explicitly contain them. It is very unlikely that this
+behaviour would ever cause problems, but if it does you can change
+it by enabling \q{Consider proxying local host connections}.
+
+Note that if you are doing DNS at the proxy (see
+\k{config-proxy-dns}), you should make sure that your proxy
+exclusion settings do not depend on knowing the IP address of a
+host. If the name is passed on to the proxy without PuTTY looking it
+up, it will never know the IP address and cannot check it against
+your list.
+
+\S{config-proxy-dns} Name resolution when using a proxy
+
+\cfg{winhelp-topic}{proxy.dns}
+
+If you are using a proxy to access a private network, it can make a
+difference whether DNS name resolution is performed by PuTTY itself
+(on the client machine) or performed by the proxy.
+
+The \q{Do DNS name lookup at proxy end} configuration option allows
+you to control this. If you set it to \q{No}, PuTTY will always do
+its own DNS, and will always pass an IP address to the proxy. If you
+set it to \q{Yes}, PuTTY will always pass host names straight to the
+proxy without trying to look them up first.
+
+If you set this option to \q{Auto} (the default), PuTTY will do
+something it considers appropriate for each type of proxy. Telnet
+and HTTP proxies will have host names passed straight to them; SOCKS
+proxies will not.
+
+Note that if you are doing DNS at the proxy, you should make sure
+that your proxy exclusion settings (see \k{config-proxy-exclude}) do
+not depend on knowing the IP address of a host. If the name is
+passed on to the proxy without PuTTY looking it up, it will never
+know the IP address and cannot check it against your list.
+
+The original SOCKS 4 protocol does not support proxy-side DNS. There
+is a protocol extension (SOCKS 4A) which does support it, but not
+all SOCKS 4 servers provide this extension. If you enable proxy DNS
+and your SOCKS 4 server cannot deal with it, this might be why.
+
+\S{config-proxy-auth} Username and password
+
+\cfg{winhelp-topic}{proxy.auth}
+
+If your proxy requires authentication, you can enter a username and
+a password in the \q{Username} and \q{Password} boxes.
+
+Authentication is not supported for all forms of proxy:
+
+\b Username and password authentication is supported for HTTP
+proxies and SOCKS 5 proxies.
+
+\b SOCKS 4 can use the \q{Username} field, but does not support
+passwords.
+
+\b You can specify a way to include a username and password in the
+Telnet proxy command (see \k{config-proxy-command}).
+
+\S{config-proxy-command} Specifying the Telnet proxy command
+
+\cfg{winhelp-topic}{proxy.command}
+
+If you are using the Telnet proxy type, the usual command required
+by the firewall's Telnet server is \c{connect}, followed by a host
+name and a port number. If your proxy needs a different command,
+you can enter an alternative here.
+
+In this string, you can use \c{\\n} to represent a new-line, \c{\\r}
+to represent a carriage return, \c{\\t} to represent a tab
+character, and \c{\\x} followed by two hex digits to represent any
+other character. \c{\\\\} is used to encode the \c{\\} character
+itself.
+
+Also, the special strings \c{%host} and \c{%port} will be replaced
+by the host name and port number you want to connect to. The strings
+\c{%user} and \c{%pass} will be replaced by the proxy username and
+password you specify. To get a literal \c{%} sign, enter \c{%%}.
+
+If the Telnet proxy server prompts for a username and password
+before commands can be sent, you can use a command such as:
+
+\c %user\\n%pass\\nconnect %host %port\\n
+
+This will send your username and password as the first two lines to
+the proxy, followed by a command to connect to the desired host and
+port. Note that if you do not include the \c{%user} or \c{%pass}
+tokens in the Telnet command, then the \q{Username} and \q{Password}
+configuration fields will be ignored.
+
+\S{config-proxy-socksver} Selecting the version of the SOCKS protocol
+
+\cfg{winhelp-topic}{proxy.socksver}
+
+SOCKS servers exist in two versions: version 5
+(\W{http://www.ietf.org/rfc/rfc1928.txt}{RFC 1928}) and the earlier
+version 4. The \q{SOCKS Version} radio buttons allow you to select
+which one to use, if you have selected the SOCKS proxy type.
+
\H{config-telnet} The Telnet panel
The Telnet panel allows you to configure options that only apply to
\S{config-termspeed} \q{Terminal-speed string}
+\cfg{winhelp-topic}{telnet.termspeed}
+
Telnet allows the client to send a text string that describes the
terminal speed. PuTTY lets you configure this, in case you find the
server is reacting badly to the default value. (I'm not aware of any
\S{config-environ} Setting environment variables on the server
+\cfg{winhelp-topic}{telnet.environ}
+
The Telnet protocol also provides a means for the client to pass
environment variables to the server. Many Telnet servers have
stopped supporting this feature due to security flaws, but PuTTY
\S{config-oldenviron} \q{Handling of OLD_ENVIRON ambiguity}
+\cfg{winhelp-topic}{telnet.oldenviron}
+
The original Telnet mechanism for passing environment variables was
badly specified. At the time the standard (RFC 1408) was written,
BSD telnet implementations were already supporting the feature, and
\S{config-ptelnet} Passive and active Telnet negotiation modes
+\cfg{winhelp-topic}{telnet.passive}
+
In a Telnet connection, there are two types of data passed between
the client and the server: actual text, and \e{negotiations} about
which Telnet extra features to use.
\S{config-telnetkey} \q{Keyboard sends telnet Backspace and Interrupt}
+\cfg{winhelp-topic}{telnet.specialkeys}
+
If this box is checked, the Backspace key on the keyboard will send
the Telnet special backspace code, and Control-C will send the
Telnet special interrupt code. You probably shouldn't enable this
unless you know what you're doing.
+\S{config-telnetnl} \q{Return key sends telnet New Line instead of ^M}
+
+\cfg{winhelp-topic}{telnet.newline}
+
+Unlike most other remote login protocols, the Telnet protocol has a
+special \q{new line} code that is not the same as the usual line
+endings of Control-M or Control-J. By default, PuTTY sends the
+Telnet New Line code when you press Return, instead of sending
+Control-M as it does in most other protocols.
+
+Most Unix-style Telnet servers don't mind whether they receive
+Telnet New Line or Control-M; some servers do expect New Line, and
+some servers prefer to see ^M. If you are seeing surprising
+behaviour when you press Return in a Telnet session, you might try
+turning this option off to see if it helps.
+
\H{config-rlogin} The Rlogin panel
The Rlogin panel allows you to configure options that only apply to
\S{config-rlogin-termspeed} \q{Terminal-speed string}
+\cfg{winhelp-topic}{rlogin.termspeed}
+
Like Telnet, Rlogin allows the client to send a text string that
describes the terminal speed. PuTTY lets you configure this, in case
you find the server is reacting badly to the default value. (I'm not
\S{config-rlogin-localuser} \q{Local username}
+\cfg{winhelp-topic}{rlogin.localuser}
+
Rlogin allows an automated (password-free) form of login by means of
a file called \c{.rhosts} on the server. You put a line in your
\c{.rhosts} file saying something like \c{jbloggs@pc1.example.com},
\S{config-command} Executing a specific command on the server
+\cfg{winhelp-topic}{ssh.command}
+
In SSH, you don't have to run a general shell session on the server.
Instead, you can choose to run a single specific command (such as a
mail user agent, for example). If you want to do this, enter the
\S{config-ssh-pty} \q{Don't allocate a pseudo-terminal}
+\cfg{winhelp-topic}{ssh.nopty}
+
When connecting to a Unix system, most interactive shell sessions
are run in a \e{pseudo-terminal}, which allows the Unix system to
pretend it's talking to a real physical terminal device but allows
\S{config-ssh-comp} \q{Enable compression}
+\cfg{winhelp-topic}{ssh.compress}
+
This enables data compression in the SSH connection: data sent by
the server is compressed before sending, and decompressed at the
client end. Likewise, data sent by PuTTY to the server is compressed
\S{config-ssh-prot} \q{Preferred SSH protocol version}
+\cfg{winhelp-topic}{ssh.protocol}
+
This allows you to select whether you would like to use SSH protocol
version 1 or version 2. \#{FIXME: say something about this elsewhere?}
PuTTY will attempt to use protocol 1 if the server you connect to
does not offer protocol 2, and vice versa.
-\S{config-ssh-macbug} \q{Imitate SSH 2 MAC bug}
-
-This option \e{should} now be unnecessary. It existed in order to
-work around a bug in early versions (2.3.0 and below) of the SSH
-server software from \cw{ssh.com}. The symptom of this problem would
-be that PuTTY would die unexpectedly at the beginning of the
-session, saying \q{Incorrect MAC received on packet}.
-
-Current versions of PuTTY attempt to detect these faulty servers and
-enable the bug compatibility automatically, so you should never need
-to use this option any more.
+If you select \q{1 only} or \q{2 only} here, PuTTY will only connect
+if the server you connect to offers the SSH protocol version you
+have specified.
\S{config-ssh-encryption} Encryption algorithm selection
+\cfg{winhelp-topic}{ssh.ciphers}
+
PuTTY supports a variety of different encryption algorithms, and
allows you to choose which one you prefer to use. You can do this by
-dragging the algorithms up and down in the list box to specify a
-preference order. When you make an SSH connection, PuTTY will search
-down the list from the top until it finds an algorithm supported by
-the server, and then use that.
+dragging the algorithms up and down in the list box (or moving them
+using the Up and Down buttons) to specify a preference order. When
+you make an SSH connection, PuTTY will search down the list from the
+top until it finds an algorithm supported by the server, and then
+use that.
If the algorithm PuTTY finds is below the \q{warn below here} line,
you will see a warning box when you make the connection:
This warns you that the first available encryption is not a very
secure one. Typically you would put the \q{warn below here} line
between the encryptions you consider secure and the ones you
-consider substandard.
-
-By default, PuTTY supplies a preference order intended to reflect a
-reasonable preference in terms of security and speed.
+consider substandard. By default, PuTTY supplies a preference order
+intended to reflect a reasonable preference in terms of security and
+speed.
+
+In SSH-2, the encryption algorithm is negotiated independently for
+each direction of the connection, although PuTTY does not support
+separate configuration of the preference orders. As a result you may
+get two warnings similar to the one above, possibly with different
+encryptions.
+
+Single-DES is not supported natively in the SSH 2 draft protocol
+standards. One or two server implementations do support it, by a
+non-standard name. PuTTY can use single-DES to interoperate with
+these servers if you enable the \q{Enable non-standard single-DES in
+SSH 2} option; by default this is disabled and PuTTY will stick to
+the standard.
\H{config-ssh-auth} The Auth panel
\S{config-ssh-tis} \q{Attempt TIS or CryptoCard authentication}
+\cfg{winhelp-topic}{ssh.auth.tis}
+
TIS and CryptoCard authentication are simple challenge/response
forms of authentication available in SSH protocol version 1 only.
You might use them if you were using S/Key one-time passwords, for
administrator about precisely what form these challenges and
responses take.
+\S{config-ssh-ki} \q{Attempt keyboard-interactive authentication}
+
+\cfg{winhelp-topic}{ssh.auth.ki}
+
+The SSH 2 equivalent of TIS authentication is called
+\q{keyboard-interactive}. It is a flexible authentication method
+using an arbitrary sequence of requests and responses; so it is not
+only useful for challenge/response mechanisms such as S/Key, but it
+can also be used for (for example) asking the user for a new
+password when the old one has expired.
+
+PuTTY leaves this option enabled by default, but supplies a switch
+to turn it off in case you should have trouble with it.
+
\S{config-ssh-agentfwd} \q{Allow agent forwarding}
+\cfg{winhelp-topic}{ssh.auth.agentfwd}
+
This option allows the SSH server to open forwarded connections back
to your local copy of Pageant. If you are not running Pageant, this
option will do nothing.
there is a security risk involved with enabling this option; see
\k{pageant-security} for details.
+\S{config-ssh-changeuser} \q{Allow attempted changes of username in SSH2}
+
+\cfg{winhelp-topic}{ssh.auth.changeuser}
+
+In the SSH 1 protocol, it is impossible to change username after
+failing to authenticate. So if you mis-type your username at the
+PuTTY \q{login as:} prompt, you will not be able to change it except
+by restarting PuTTY.
+
+The SSH 2 protocol \e{does} allow changes of username, in principle,
+but does not make it mandatory for SSH 2 servers to accept them. In
+particular, OpenSSH does not accept a change of username; once you
+have sent one username, it will reject attempts to try to
+authenticate as another user. (Depending on the version of OpenSSH,
+it may quietly return failure for all login attempts, or it may send
+an error message.)
+
+For this reason, PuTTY will by default not prompt you for your
+username more than once, in case the server complains. If you know
+your server can cope with it, you can enable the \q{Allow attempted
+changes of username} option to modify PuTTY's behaviour.
+
\S{config-ssh-privkey} \q{Private key file for authentication}
+\cfg{winhelp-topic}{ssh.auth.privkey}
+
This box is where you enter the name of your private key file if you
are using public key authentication. See \k{pubkey} for information
about public key authentication in SSH.
\S{config-ssh-x11} X11 forwarding
+\cfg{winhelp-topic}{ssh.tunnels.x11}
+
If your server lets you run X Window System applications, X11
forwarding allows you to securely give those applications access to
a local X display on your PC.
-This feature will only be useful if you have an X server on your PC,
-such as Exceed or XWin32.
-
To enable X11 forwarding, check the \q{Enable X11 forwarding} box.
If your X display is not the primary display on your local machine
(which it almost certainly will be unless you have deliberately
arranged otherwise), you need to enter its location in the \q{X
display location} box.
-\# FIXME: perhaps link to some more general X forwarding info?
+See \k{using-x-forwarding} for more information about X11
+forwarding.
\S{config-ssh-portfwd} Port forwarding
+\cfg{winhelp-topic}{ssh.tunnels.portfwd}
+
Port forwarding allows you to tunnel other types of network
-connection down an SSH connection.
-
-To set up a local port forwarding, make sure the \q{Local} radio
-button is set. Then enter a local port number (on your PC) in the
-\q{Source port} box, and a hostname and port number (separated by a
-colon) in the \q{Destination} box, and finally press the \q{Add}
-button. For example, you might select a source port of 10079, and a
-destination of \c{server2.example.com:79}.
-
-If you do this, and then start the session, you should find that
-connecting to your local PC on port 10079 gives you a connection to
-port 79 (the finger server) on \c{server2.example.com}. The
-connection is actually going to PuTTY itself, which encrypts the
-connection data and sends it down the secure channel to the SSH
-server. The connection then proceeds in clear from there to the
-eventual destination. So you might use this (for example) to forward
-a connection between two non-hostile network zones that are only
-connected by a hostile zone such as the open Internet.
-
-You can forward ports on the SSH server machine in the other
-direction, too (so the connection will start at the server end and
-be sent down the secure connection to PuTTY, which will make the
-real connection to the destination). To work this way round, just
-click the \q{Remote} radio button instead of \q{Local}.
-
-\# FIXME: perhaps move this to a general port-forwarding section and
-\# just link to it here?
+connection down an SSH session. See \k{using-port-forwarding} for a
+general discussion of port forwarding and how it works.
+
+The port forwarding section in the Tunnels panel shows a list of all
+the port forwardings that PuTTY will try to set up when it connects
+to the server. By default no port forwardings are set up, so this
+list is empty.
+
+To add a port forwarding:
+
+\b Set one of the \q{Local} or \q{Remote} radio buttons, depending
+on whether you want to forward a local port to a remote destination
+(\q{Local}) or forward a remote port to a local destination
+(\q{Remote}).
+
+\b Enter a source port number into the \q{Source port} box. For
+local forwardings, PuTTY will listen on this port of your PC. For
+remote forwardings, your SSH server will listen on this port of the
+remote machine. Note that most servers will not allow you to listen
+on port numbers less than 1024.
+
+\b Enter a hostname and port number separated by a colon, in the
+\q{Destination} box. Connections received on the source port will be
+directed to this destination. For example, to connect to a POP-3
+server, you might enter \c{popserver.example.com:110}.
+
+\b Click the \q{Add} button. Your forwarding details should appear
+in the list box.
+
+To remove a port forwarding, simply select its details in the list
+box, and click the \q{Remove} button.
+
+In the \q{Source port} box, you can also optionally enter an IP
+address to listen on. Typically a Windows machine can be asked to
+listen on any single IP address in the \cw{127.*.*.*} range, and all
+of these are loopback addresses available only to the local machine.
+So if you forward (for example) \c{127.0.0.5:79} to a remote
+machine's \cw{finger} port, then you should be able to run commands
+such as \c{finger fred@127.0.0.5}. This can be useful if the program
+connecting to the forwarded port doesn't allow you to change the
+port number it uses. This feature is available for local-to-remote
+forwarded ports; SSH1 is unable to support it for remote-to-local
+ports, while SSH2 can support it in theory but servers will not
+necessarily cooperate.
+
+\S{config-ssh-portfwd-localhost} Controlling the visibility of
+forwarded ports
+
+\cfg{winhelp-topic}{ssh.tunnels.portfwd.localhost}
+
+The source port for a forwarded connection usually does not accept
+connections from any machine except the SSH client or server machine
+itself (for local and remote forwardings respectively). There are
+controls in the Tunnels panel to change this:
+
+\b The \q{Local ports accept connections from other hosts} option
+allows you to set up local-to-remote port forwardings in such a way
+that machines other than your client PC can connect to the forwarded
+port.
+
+\b The \q{Remote ports do the same} option does the same thing for
+remote-to-local port forwardings (so that machines other than the
+SSH server machine can connect to the forwarded port.) Note that
+this feature is only available in the SSH 2 protocol, and not all
+SSH 2 servers support it (OpenSSH 3.0 does not, for example).
+
+\H{config-ssh-bugs} The Bugs panel
+
+Not all SSH servers work properly. Various existing servers have
+bugs in them, which can make it impossible for a client to talk to
+them unless it knows about the bug and works around it.
+
+Since most servers announce their software version number at the
+beginning of the SSH connection, PuTTY will attempt to detect which
+bugs it can expect to see in the server and automatically enable
+workarounds. However, sometimes it will make mistakes; if the server
+has been deliberately configured to conceal its version number, or
+if the server is a version which PuTTY's bug database does not know
+about, then PuTTY will not know what bugs to expect.
+
+The Bugs panel allows you to manually configure the bugs PuTTY
+expects to see in the server. Each bug can be configured in three
+states:
+
+\b \q{Off}: PuTTY will assume the server does not have the bug.
+
+\b \q{On}: PuTTY will assume the server \e{does} have the bug.
+
+\b \q{Auto}: PuTTY will use the server's version number announcement
+to try to guess whether or not the server has the bug.
+
+\S{config-ssh-bug-ignore1} \q{Chokes on SSH1 ignore messages}
+
+\cfg{winhelp-topic}{ssh.bugs.ignore1}
+
+An ignore message (SSH_MSG_IGNORE) is a message in the SSH protocol
+which can be sent from the client to the server, or from the server
+to the client, at any time. Either side is required to ignore the
+message whenever it receives it. PuTTY uses ignore messages to hide
+the password packet in SSH1, so that a listener cannot tell the
+length of the user's password; it also uses ignore messages for
+connection keepalives (see \k{config-keepalive}).
+
+If this bug is detected, PuTTY will stop using ignore messages. This
+means that keepalives will stop working, and PuTTY will have to fall
+back to a secondary defence against SSH1 password-length
+eavesdropping. See \k{config-ssh-bug-plainpw1}. If this bug is
+enabled when talking to a correct server, the session will succeed,
+but keepalives will not work and the session might be more
+vulnerable to eavesdroppers than it could be.
+
+This is an SSH1-specific bug. No known SSH2 server fails to deal
+with SSH2 ignore messages.
+
+\S{config-ssh-bug-plainpw1} \q{Refuses all SSH1 password camouflage}
+
+\cfg{winhelp-topic}{ssh.bugs.plainpw1}
+
+When talking to an SSH1 server which cannot deal with ignore
+messages (see \k{config-ssh-bug-ignore1}), PuTTY will attempt to
+disguise the length of the user's password by sending additional
+padding \e{within} the password packet. This is technically a
+violation of the SSH1 specification, and so PuTTY will only do it
+when it cannot use standards-compliant ignore messages as
+camouflage. In this sense, for a server to refuse to accept a padded
+password packet is not really a bug, but it does make life
+inconvenient if the server can also not handle ignore messages.
+
+If this \q{bug} is detected, PuTTY will have no choice but to send
+the user's password with no form of camouflage, so that an
+eavesdropping user will be easily able to find out the exact length
+of the password. If this bug is enabled when talking to a correct
+server, the session will succeed, but will be more vulnerable to
+eavesdroppers than it could be.
+
+This is an SSH1-specific bug. SSH2 is secure against this type of
+attack.
+
+\S{config-ssh-bug-rsa1} \q{Chokes on SSH1 RSA authentication}
+
+\cfg{winhelp-topic}{ssh.bugs.rsa1}
+
+Some SSH1 servers cannot deal with RSA authentication messages at
+all. If Pageant is running and contains any SSH1 keys, PuTTY will
+normally automatically try RSA authentication before falling back to
+passwords, so these servers will crash when they see the RSA attempt.
+
+If this bug is detected, PuTTY will go straight to password
+authentication. If this bug is enabled when talking to a correct
+server, the session will succeed, but of course RSA authentication
+will be impossible.
+
+This is an SSH1-specific bug.
+
+\S{config-ssh-bug-hmac2} \q{Miscomputes SSH2 HMAC keys}
+
+\cfg{winhelp-topic}{ssh.bugs.hmac2}
+
+Versions 2.3.0 and below of the SSH server software from
+\cw{ssh.com} compute the keys for their HMAC message authentication
+codes incorrectly. A typical symptom of this problem is that PuTTY
+dies unexpectedly at the beginning of the session, saying
+\q{Incorrect MAC received on packet}.
+
+If this bug is detected, PuTTY will compute its HMAC keys in the
+same way as the buggy server, so that communication will still be
+possible. If this bug is enabled when talking to a correct server,
+communication will fail.
+
+This is an SSH2-specific bug.
+
+\S{config-ssh-bug-derivekey2} \q{Miscomputes SSH2 encryption keys}
+
+\cfg{winhelp-topic}{ssh.bugs.derivekey2}
+
+Versions below 2.1.0 of the SSH server software from \cw{ssh.com}
+compute the keys for the session encryption incorrectly. This
+problem can cause various error messages, such as \q{Incoming packet
+was garbled on decryption}, or possibly even \q{Out of memory}.
+
+If this bug is detected, PuTTY will compute its encryption keys in
+the same way as the buggy server, so that communication will still
+be possible. If this bug is enabled when talking to a correct
+server, communication will fail.
+
+This is an SSH2-specific bug.
+
+\S{config-ssh-bug-sig} \q{Requires padding on SSH2 RSA signatures}
+
+\cfg{winhelp-topic}{ssh.bugs.rsapad2}
+
+Versions below 3.3 of OpenSSH require SSH2 RSA signatures to be
+padded with zero bytes to the same length as the RSA key modulus.
+The SSH2 draft specification says that an unpadded signature MUST be
+accepted, so this is a bug. A typical symptom of this problem is
+that PuTTY mysteriously fails RSA authentication once in every few
+hundred attempts, and falls back to passwords.
+
+If this bug is detected, PuTTY will pad its signatures in the way
+OpenSSH expects. If this bug is enabled when talking to a correct
+server, it is likely that no damage will be done, since correct
+servers usually still accept padded signatures because they're used
+to talking to OpenSSH.
+
+This is an SSH2-specific bug.
+
+\S{config-ssh-bug-dhgex} \q{Chokes on Diffie-Hellman group exchange}
+
+\cfg{winhelp-topic}{ssh.bugs.dhgex2}
+
+We have anecdotal evidence that some SSH servers claim to be able to
+perform Diffie-Hellman group exchange, but fail to actually do so
+when PuTTY tries to. If your SSH2 sessions spontaneously close
+immediately after opening the PuTTY window, it might be worth
+enabling the workaround for this bug to see if it helps.
+
+We have no hard evidence that any specific version of specific
+server software reliably demonstrates this bug. Therefore, PuTTY
+will never \e{assume} a server has this bug; if you want the
+workaround, you need to enable it manually.
+
+This is an SSH2-specific bug.
\H{config-file} Storing configuration in a file
projects / u / mdw / putty / blobdiff