| 1 | \C{config} Configuring PuTTY |
| 2 | |
| 3 | This chapter describes all the configuration options in PuTTY. |
| 4 | |
| 5 | PuTTY is configured using the control panel that comes up before you |
| 6 | start a session. Some options can also be changed in the middle of a |
| 7 | session, by selecting \e{Change Settings} from the window menu. |
| 8 | |
| 9 | \H{config-session} The Session panel |
| 10 | |
| 11 | The Session configuration panel contains the basic options you need |
| 12 | to specify in order to open a session at all, and also allows you to |
| 13 | save your settings to be reloaded later. |
| 14 | |
| 15 | \S{config-hostname} The host name section |
| 16 | |
| 17 | The top box on the Session panel, labelled \q{Specify your |
| 18 | connection by host name}, contains the details that need to be |
| 19 | filled in before PuTTY can open a session at all. |
| 20 | |
| 21 | \b The \e{Host Name} box is where you type the name, or the IP |
| 22 | address, of the server you want to connect to. |
| 23 | |
| 24 | \b The \e{Protocol} radio buttons let you choose what type of |
| 25 | connection you want to make: a raw connection, a Telnet connection, an |
| 26 | rlogin connection or an SSH connection. (See \k{which-one} for a |
| 27 | summary of the differences between SSH, Telnet and rlogin.) |
| 28 | |
| 29 | \b The \e{Port} box lets you specify which port number on the server |
| 30 | to connect to. If you select Telnet, Rlogin, or SSH, this box will be |
| 31 | filled in automatically to the usual value, and you will only need to |
| 32 | change it if you have an unusual server. If you select Raw mode, you |
| 33 | will almost certainly need to fill in the \e{Port} box. |
| 34 | |
| 35 | \S{config-saving} Loading and storing saved sessions |
| 36 | |
| 37 | The next part of the Session configuration panel allows you to save |
| 38 | your preferred PuTTY options so they will appear automatically the |
| 39 | next time you start PuTTY. It also allows you to create \e{saved |
| 40 | sessions}, which contain a full set of configuration options plus a |
| 41 | host name and protocol. A saved session contains all the information |
| 42 | PuTTY needs to start exactly the session you want. |
| 43 | |
| 44 | \b To save your default settings: first set up the settings the way |
| 45 | you want them saved. Then come back to the Session panel. Select the |
| 46 | \q{Default Settings} entry in the saved sessions list, with a single |
| 47 | click. Then press the \e{Save} button. |
| 48 | |
| 49 | Note that PuTTY does not allow you to save a host name into the |
| 50 | Default Settings entry. This ensures that when PuTTY is started up, |
| 51 | the host name box is always empty, so a user can always just type in |
| 52 | a host name and connect. |
| 53 | |
| 54 | If there is a specific host you want to store the details of how to |
| 55 | connect to, you should create a saved session, which will be |
| 56 | separate from the Default Settings. |
| 57 | |
| 58 | \b To save a session: first go through the rest of the configuration |
| 59 | box setting up all the options you want. Then come back to the |
| 60 | Session panel. Enter a name for the saved session in the \e{Saved |
| 61 | Sessions} input box. (The server name is often a good choice for a |
| 62 | saved session name.) Then press the \e{Save} button. Your saved |
| 63 | session name should now appear in the list box. |
| 64 | |
| 65 | \b To reload a saved session: single-click to select the session |
| 66 | name in the list box, and then press the \e{Load} button. Your saved |
| 67 | settings should all appear in the configuration panel. |
| 68 | |
| 69 | \b To modify a saved session: first load it as described above. Then |
| 70 | make the changes you want. Come back to the Session panel, |
| 71 | single-click to select the session name in the list box, and press |
| 72 | the \e{Save} button. The new settings will be saved over the top of |
| 73 | the old ones. |
| 74 | |
| 75 | \b To start a saved session immediately: double-click on the session |
| 76 | name in the list box. |
| 77 | |
| 78 | \b To delete a saved session: single-click to select the session |
| 79 | name in the list box, and then press the \e{Delete} button. |
| 80 | |
| 81 | Each saved session is independent of the Default Settings |
| 82 | configuration. If you change your preferences and update Default |
| 83 | Settings, you must also update every saved session separately. |
| 84 | |
| 85 | \S{config-closeonexit} \q{Close Window on Exit} |
| 86 | |
| 87 | Finally in the Session panel, there is an option labelled \q{Close |
| 88 | Window on Exit}. This controls whether the PuTTY session window |
| 89 | disappears as soon as the session inside it terminates. If you are |
| 90 | likely to want to copy and paste text out of the session after it |
| 91 | has terminated, you should arrange this option to be off. |
| 92 | |
| 93 | \q{Close Window On Exit} has three settings. \q{Always} means always |
| 94 | close the window on exit; \q{Never} means never close on exit |
| 95 | (always leave the window open). The third setting, and the default |
| 96 | one, is \q{Only on clean exit}. In this mode, a session which |
| 97 | terminates normally will cause its window to close, but one which is |
| 98 | aborted unexpectedly by network trouble or a confusing message from |
| 99 | the server will leave the window up. |
| 100 | |
| 101 | \H{config-logging} The Logging panel |
| 102 | |
| 103 | The Logging configuration panel allows you to save log files of your |
| 104 | PuTTY sessions, for debugging, analysis or future reference. |
| 105 | |
| 106 | The main option is a radio-button set that specifies whether PuTTY |
| 107 | will log anything at all. The options are |
| 108 | |
| 109 | \b \q{Logging turned off completely}. This is the default option; in |
| 110 | this mode PuTTY will not create a log file at all. |
| 111 | |
| 112 | \b \q{Log printable output only}. In this mode, a log file will be |
| 113 | created and written to, but only printable text will be saved into |
| 114 | it. The various terminal control codes that are typically sent down |
| 115 | an interactive session alongside the printable text will be omitted. |
| 116 | This might be a useful mode if you want to read a log file in a text |
| 117 | editor and hope to be able to make sense of it. |
| 118 | |
| 119 | \b \q{Log all session output}. In this mode, \e{everything} sent by |
| 120 | the server into your terminal session is logged. If you view the log |
| 121 | file in a text editor, therefore, you may well find it full of |
| 122 | strange control characters. This is a particularly useful mode if |
| 123 | you are experiencing problems with PuTTY's terminal handling: you |
| 124 | can record everything that went to the terminal, so that someone |
| 125 | else can replay the session later in slow motion and watch to see |
| 126 | what went wrong. |
| 127 | |
| 128 | \S{config-logfilename} \q{Log file name} |
| 129 | |
| 130 | In this edit box you enter the name of the file you want to log the |
| 131 | session to. The \q{Browse} button will let you look around your file |
| 132 | system to find the right place to put the file; or if you already |
| 133 | know exactly where you want it to go, you can just type a pathname |
| 134 | into the edit box. |
| 135 | |
| 136 | There are a few special features in this box. If you use the \c{&} |
| 137 | character in the file name box, PuTTY will insert details of the |
| 138 | current session in the name of the file it actually opens. The |
| 139 | precise replacements it will do are: |
| 140 | |
| 141 | \b \c{&Y} will be replaced by the current year, as four digits. |
| 142 | |
| 143 | \b \c{&M} will be replaced by the current month, as two digits. |
| 144 | |
| 145 | \b \c{&D} will be replaced by the current day of the month, as two |
| 146 | digits. |
| 147 | |
| 148 | \b \c{&T} will be replaced by the current time, as six digits |
| 149 | (HHMMSS) with no punctuation. |
| 150 | |
| 151 | \b \c{&H} will be replaced by the host name you are connecting to. |
| 152 | |
| 153 | For example, if you enter the host name |
| 154 | \c{c:\\puttylogs\\log-&h-&y&m&d-&t.dat}, you will end up with files looking |
| 155 | like |
| 156 | |
| 157 | \c log-server1.example.com-20010528-110859.dat |
| 158 | \c log-unixbox.somewhere.org-20010611-221001.dat |
| 159 | |
| 160 | \S{config-logfileexists} \q{What to do if the log file already exists} |
| 161 | |
| 162 | This control allows you to specify what PuTTY should do if it tries |
| 163 | to start writing to a log file and it finds the file already exists. |
| 164 | You might want to automatically destroy the existing log file and |
| 165 | start a new one with the same name. Alternatively, you might want to |
| 166 | open the existing log file and add data to the \e{end} of it. |
| 167 | Finally (the default option), you might not want to have any |
| 168 | automatic behaviour, but to ask the user every time the problem |
| 169 | comes up. |
| 170 | |
| 171 | \H{config-terminal} The Terminal panel |
| 172 | |
| 173 | The Terminal configuration panel allows you to control the behaviour |
| 174 | of PuTTY's terminal emulation. |
| 175 | |
| 176 | \S{config-autowrap} \q{Auto wrap mode initially on} |
| 177 | |
| 178 | Auto wrap mode controls what happens when text printed in a PuTTY |
| 179 | window reaches the right-hand edge of the window. |
| 180 | |
| 181 | With auto wrap mode on, if a long line of text reaches the |
| 182 | right-hand edge, it will wrap over on to the next line so you can |
| 183 | still see all the text. With auto wrap mode off, the cursor will |
| 184 | stay at the right-hand edge of the screen, and all the characters in |
| 185 | the line will be printed on top of each other. |
| 186 | |
| 187 | If you are running a full-screen application and you occasionally |
| 188 | find the screen scrolling up when it looks as if it shouldn't, you |
| 189 | could try turning this option off. |
| 190 | |
| 191 | Auto wrap mode can be turned on and off by control sequences sent by |
| 192 | the server. This configuration option only controls the \e{default} |
| 193 | state. If you modify this option in mid-session using \e{Change |
| 194 | Settings}, you will need to reset the terminal \#{ FIXME } before |
| 195 | the change takes effect. |
| 196 | |
| 197 | \S{config-decom} \q{DEC Origin Mode initially on} |
| 198 | |
| 199 | DEC Origin Mode is a minor option which controls how PuTTY |
| 200 | interprets cursor-position control sequences sent by the server. |
| 201 | |
| 202 | The server can send a control sequence that restricts the scrolling |
| 203 | region of the display. For example, in an editor, the server might |
| 204 | reserve a line at the top of the screen and a line at the bottom, |
| 205 | and might send a control sequence that causes scrolling operations |
| 206 | to affect only the remaining lines. |
| 207 | |
| 208 | With DEC Origin Mode on, cursor coordinates are counted from the top |
| 209 | of the scrolling region. With it turned off, cursor coordinates are |
| 210 | counted from the top of the whole screen regardless of the scrolling |
| 211 | region. |
| 212 | |
| 213 | It is unlikely you would need to change this option, but if you find |
| 214 | a full-screen application is displaying pieces of text in what looks |
| 215 | like the wrong part of the screen, you could try turning DEC Origin |
| 216 | Mode on to see whether that helps. |
| 217 | |
| 218 | DEC Origin Mode can be turned on and off by control sequences sent by |
| 219 | the server. This configuration option only controls the \e{default} |
| 220 | state. If you modify this option in mid-session using \e{Change |
| 221 | Settings}, you will need to reset the terminal \#{ FIXME } before |
| 222 | the change takes effect. |
| 223 | |
| 224 | \S{config-crlf} \q{Implicit CR in every LF} |
| 225 | |
| 226 | Most servers send two control characters, CR and LF, to start a new |
| 227 | line of the screen. The CR character makes the cursor return to the |
| 228 | left-hand side of the screen. The LF character makes the cursor move |
| 229 | one line down (and might make the screen scroll). |
| 230 | |
| 231 | Some servers only send LF, and expect the terminal to move the |
| 232 | cursor over to the left automatically. If you come across a server |
| 233 | that does this, you will see a stepped effect on the screen, like |
| 234 | this: |
| 235 | |
| 236 | \c First line of text |
| 237 | \c Second line |
| 238 | \c Third line |
| 239 | |
| 240 | If this happens to you, try enabling the \q{Implicit CR in every LF} |
| 241 | option, and things might go back to normal: |
| 242 | |
| 243 | \c First line of text |
| 244 | \c Second line |
| 245 | \c Third line |
| 246 | |
| 247 | \S{config-erase} \q{Use background colour to erase screen} |
| 248 | |
| 249 | Not all terminals agree on what colour to turn the screen when the |
| 250 | server sends a \q{clear screen} sequence. Some terminals believe the |
| 251 | screen should always be cleared to the \e{default} background |
| 252 | colour. Others believe the screen should be cleared to whatever the |
| 253 | server has selected as a background colour. |
| 254 | |
| 255 | There exist applications that expect both kinds of behaviour. |
| 256 | Therefore, PuTTY can be configured to do either. |
| 257 | |
| 258 | With this option disabled, screen clearing is always done in the |
| 259 | default background colour. With this option enabled, it is done in |
| 260 | the \e{current} background colour. |
| 261 | |
| 262 | \S{config-blink} \q{Enable blinking text} |
| 263 | |
| 264 | The server can ask PuTTY to display text that blinks on and off. |
| 265 | This is very distracting, so PuTTY allows you to turn blinking text |
| 266 | off completely. |
| 267 | |
| 268 | \S{config-localecho} \q{Local echo} |
| 269 | |
| 270 | With local echo disabled, characters you type into the PuTTY window |
| 271 | are not echoed in the window \e{by PuTTY}. They are simply sent to |
| 272 | the server. (The \e{server} might choose to echo them back to you; |
| 273 | this can't be controlled from the PuTTY control panel.) |
| 274 | |
| 275 | Some types of session need local echo, and many do not. In its |
| 276 | default mode, PuTTY will automatically attempt to deduce whether or |
| 277 | not local echo is appropriate for the session you are working in. If |
| 278 | you find it has made the wrong decision, you can use this |
| 279 | configuration option to override its choice: you can force local |
| 280 | echo to be turned on, or force it to be turned off, instead of |
| 281 | relying on the automatic detection. |
| 282 | |
| 283 | \S{config-localedit} \q{Local line editing} |
| 284 | |
| 285 | Normally, every character you type into the PuTTY window is sent |
| 286 | immediately to the server the moment you type it. |
| 287 | |
| 288 | If you enable local line editing, this changes. PuTTY will let you |
| 289 | edit a whole line at a time locally, and the line will only be sent |
| 290 | to the server when you press Return. If you make a mistake, you can |
| 291 | use the Backspace key to correct it before you press Return, and the |
| 292 | server will never see the mistake. |
| 293 | |
| 294 | Since it is hard to edit a line locally without being able to see |
| 295 | it, local line editing is mostly used in conjunction with local echo |
| 296 | (\k{config-localecho}). This makes it ideal for use in raw mode |
| 297 | \#{FIXME} or when connecting to MUDs or talkers. (Although some more |
| 298 | advanced MUDs do occasionally turn local line editing on and turn |
| 299 | local echo off, in order to accept a password from the user.) |
| 300 | |
| 301 | Some types of session need local line editing, and many do not. In |
| 302 | its default mode, PuTTY will automatically attempt to deduce whether |
| 303 | or not local line editing is appropriate for the session you are |
| 304 | working in. If you find it has made the wrong decision, you can use |
| 305 | this configuration option to override its choice: you can force |
| 306 | local line editing to be turned on, or force it to be turned off, |
| 307 | instead of relying on the automatic detection. |
| 308 | |
| 309 | \H{config-bell} The Bell panel |
| 310 | |
| 311 | The Bell panel controls the terminal bell feature: the server's |
| 312 | ability to cause PuTTY to beep at you. |
| 313 | |
| 314 | In the default configuration, when the server sends the character |
| 315 | with ASCII code 7 (Control-G), PuTTY will play the Windows Default |
| 316 | Beep sound. This is not always what you want the terminal bell |
| 317 | feature to do; the Bell panel allows you to configure alternative |
| 318 | actions. |
| 319 | |
| 320 | \S{config-bellstyle} \q{Set the style of bell} |
| 321 | |
| 322 | This control allows you to select various different actions to occur |
| 323 | on a terminal bell: |
| 324 | |
| 325 | \b Selecting \q{None} disables the bell completely. In this mode, |
| 326 | the server can send as many Control-G characters as it likes and |
| 327 | nothing at all will happen. |
| 328 | |
| 329 | \b \q{Play Windows Default Sound} is the default setting. It causes |
| 330 | the Windows \q{Default Beep} sound to be played. To change what this |
| 331 | sound is, or to test it if nothing seems to be happening, use the |
| 332 | Sound configurer in the Windows Control Panel. |
| 333 | |
| 334 | \b \q{Play a custom sound file} allows you to specify a particular |
| 335 | sound file to be used by PuTTY alone, or even by a particular |
| 336 | individual PuTTY session. This allows you to distinguish your PuTTY |
| 337 | beeps from any other beeps on the system. If you select this option, |
| 338 | you will also need to enter the name of your sound file in the edit |
| 339 | control \q{Custom sound file to play as a bell}. |
| 340 | |
| 341 | \b \q{Visual bell} is a silent alternative to a beeping computer. In |
| 342 | this mode, when the server sends a Control-G, the whole PuTTY window |
| 343 | will flash white for a fraction of a second. |
| 344 | |
| 345 | \S{config-belltaskbar} \q{Taskbar/caption indication on bell} |
| 346 | |
| 347 | This feature controls what happens to the PuTTY window's entry in |
| 348 | the Windows Taskbar if a bell occurs while the window does not have |
| 349 | the input focus. |
| 350 | |
| 351 | In the default state (\q{Disabled}) nothing unusual happens. |
| 352 | |
| 353 | If you select \q{Steady}, then when a bell occurs and the window is |
| 354 | not in focus, the window's Taskbar entry and its title bar will |
| 355 | change colour to let you know that PuTTY session is asking for your |
| 356 | attention. The change of colour will persist until you select the |
| 357 | window, so you can leave several PuTTY windows minimised in your |
| 358 | terminal, go away from your keyboard, and be sure not to have missed |
| 359 | any important beeps when you get back. |
| 360 | |
| 361 | \q{Flashing} is even more eye-catching: the Taskbar entry will |
| 362 | continuously flash on and off until you select the window. |
| 363 | |
| 364 | \S{config-bellovl} \q{Control the bell overload behaviour} |
| 365 | |
| 366 | A common user error in a terminal session is to accidentally run the |
| 367 | Unix command \c{cat} (or equivalent) on an inappropriate file type, |
| 368 | such as an executable, image file, or ZIP file. This produces a huge |
| 369 | stream of non-text characters sent to the terminal, which typically |
| 370 | includes a lot of bell characters. As a result of this the terminal |
| 371 | often doesn't stop beeping for ten minutes, and everybody else in |
| 372 | the office gets annoyed. |
| 373 | |
| 374 | To try to avoid this behaviour, or any other cause of excessive |
| 375 | beeping, PuTTY includes a bell overload management feature. In the |
| 376 | default configuration, receiving more than five bell characters in a |
| 377 | two-second period will cause the overload feature to activate. Once |
| 378 | the overload feature is active, further bells will have no effect at |
| 379 | all, so the rest of your binary file will be sent to the screen in |
| 380 | silence. After a period of five seconds during which no further |
| 381 | bells are received, the overload feature will turn itself off again |
| 382 | and bells will be re-enabled. |
| 383 | |
| 384 | If you want this feature completely disabled, you can turn it off |
| 385 | using the checkbox \q{Bell is temporarily disabled when over-used}. |
| 386 | |
| 387 | Alternatively, if you like the bell overload feature but don't agree |
| 388 | with the settings, you can configure the details: how many bells |
| 389 | constitute an overload, how short a time period they have to arrive |
| 390 | in to do so, and how much silent time is required before the |
| 391 | overload feature will deactivate itself. |
| 392 | |
| 393 | \H{config-keyboard} The Keyboard panel |
| 394 | |
| 395 | The Keyboard configuration panel allows you to control the behaviour |
| 396 | of the keyboard in PuTTY. |
| 397 | |
| 398 | \S{config-backspace} Changing the action of the Backspace key |
| 399 | |
| 400 | Some terminals believe that the Backspace key should send the same |
| 401 | thing to the server as Control-H (ASCII code 8). Other terminals |
| 402 | believe that the Backspace key should send ASCII code 127 (usually |
| 403 | known as Control-?) so that it can be distinguished from Control-H. |
| 404 | This option allows you to choose which code PuTTY generates when you |
| 405 | press Backspace. |
| 406 | |
| 407 | If you are connecting to a Unix system, you will probably find that |
| 408 | the Unix \c{stty} command lets you configure which the server |
| 409 | expects to see, so you might not need to change which one PuTTY |
| 410 | generates. On other systems, the server's expectation might be fixed |
| 411 | and you might have no choice but to configure PuTTY. |
| 412 | |
| 413 | If you do have the choice, we recommend configuring PuTTY to |
| 414 | generate Control-? and configuring the server to expect it, because |
| 415 | that allows applications such as \c{emacs} to use Control-H for |
| 416 | help. |
| 417 | |
| 418 | \S{config-homeend} Changing the action of the Home and End keys |
| 419 | |
| 420 | The Unix terminal emulator \c{rxvt} disagrees with the rest of the |
| 421 | world about what character sequences should be sent to the server by |
| 422 | the Home and End keys. |
| 423 | |
| 424 | \c{xterm}, and other terminals, send \c{ESC [1~} for the Home key, |
| 425 | and \c{ESC [4~} for the End key. \c{rxvt} sends \c{ESC [H} for the |
| 426 | Home key and \c{ESC [Ow} for the End key. |
| 427 | |
| 428 | If you find an application on which the Home and End keys aren't |
| 429 | working, you could try switching this option to see if it helps. |
| 430 | |
| 431 | \S{config-funkeys} Changing the action of the function keys and keypad |
| 432 | |
| 433 | This option affects the function keys (F1 to F12) and the top row of |
| 434 | the numeric keypad. |
| 435 | |
| 436 | \b In the default mode, labelled \c{ESC [n~}, the function keys |
| 437 | generate sequences like \c{ESC [11~}, \c{ESC [12~} and so on. This |
| 438 | matches the general behaviour of Digital's terminals. |
| 439 | |
| 440 | \b In Linux mode, F6 to F12 behave just like the default mode, but |
| 441 | F1 to F5 generate \c{ESC [[A} through to \c{ESC [[E}. This mimics the |
| 442 | Linux virtual console. |
| 443 | |
| 444 | \b In Xterm R6 mode, F5 to F12 behave like the default mode, but F1 |
| 445 | to F4 generate \c{ESC OP} through to \c{ESC OS}, which are the |
| 446 | sequences produced by the top row of the \e{keypad} on Digital's |
| 447 | terminals. |
| 448 | |
| 449 | \b In VT400 mode, all the function keys behave like the default |
| 450 | mode, but the actual top row of the numeric keypad generates \c{ESC |
| 451 | OP} through to \c{ESC OS}. |
| 452 | |
| 453 | \b In VT100+ mode, the function keys generate \c{ESC OP} through to |
| 454 | \c{ESC O[} |
| 455 | |
| 456 | \b In SCO mode, the function keys F1 to F12 generate \c{ESC [M} |
| 457 | through to \c{ESC [X}. Together with shift, they generate \c{ESC [Y} |
| 458 | through to \c{ESC [j}. With control they generate \c{ESC [k} through |
| 459 | to \c{ESC [v}, and with shift and control together they generate |
| 460 | \c{ESC [w} through to \c{ESC [\{}. |
| 461 | |
| 462 | If you don't know what any of this means, you probably don't need to |
| 463 | fiddle with it. |
| 464 | |
| 465 | \S{config-appcursor} Controlling Application Cursor Keys mode |
| 466 | |
| 467 | Application Cursor Keys mode is a way for the server to change the |
| 468 | control sequences sent by the arrow keys. In normal mode, the arrow |
| 469 | keys send \c{ESC [A} through to \c{ESC [D}. In application mode, |
| 470 | they send \c{ESC OA} through to \c{ESC OD}. |
| 471 | |
| 472 | Application Cursor Keys mode can be turned on and off by the server, |
| 473 | depending on the application. PuTTY allows you to configure the |
| 474 | initial state, and also allows you to disable application mode |
| 475 | completely. |
| 476 | |
| 477 | \S{config-appkeypad} Controlling Application Keypad mode |
| 478 | |
| 479 | Application Keypad mode is a way for the server to change the |
| 480 | behaviour of the numeric keypad. |
| 481 | |
| 482 | In normal mode, the keypad behaves like a normal Windows keypad: |
| 483 | with NumLock on, the number keys generate numbers, and with NumLock |
| 484 | off they act like the arrow keys and Home, End etc. |
| 485 | |
| 486 | In application mode, all the keypad keys send special control |
| 487 | sequences, \e{including} Num Lock. Num Lock stops behaving like Num |
| 488 | Lock and becomes another function key. |
| 489 | |
| 490 | Depending on which version of Windows you run, you may find the Num |
| 491 | Lock light still flashes on and off every time you press Num Lock, |
| 492 | even when application mode is active and Num Lock is acting like a |
| 493 | function key. This is unavoidable. |
| 494 | |
| 495 | Application keypad mode can be turned on and off by the server, |
| 496 | depending on the application. PuTTY allows you to configure the |
| 497 | initial state, and also allows you to disable application mode |
| 498 | completely. |
| 499 | |
| 500 | \S{config-nethack} Using NetHack keypad mode |
| 501 | |
| 502 | PuTTY has a special mode for playing NetHack. You can enable it by |
| 503 | selecting \q{NetHack} in the \q{Initial state of numeric keypad} |
| 504 | control. |
| 505 | |
| 506 | In this mode, the numeric keypad keys 1-9 generate the NetHack |
| 507 | movement commands (\cw{hjklyubn}). The 5 key generates the \c{.} |
| 508 | command (do nothing). |
| 509 | |
| 510 | Better still, pressing Shift with the keypad keys generates the |
| 511 | capital forms of the commands (\cw{HJKLYUBN}), which tells NetHack |
| 512 | to keep moving you in the same direction until you encounter |
| 513 | something interesting. |
| 514 | |
| 515 | For some reason, this feature only works properly when Num Lock is |
| 516 | on. We don't know why. |
| 517 | |
| 518 | \S{config-compose} Enabling a DEC-like Compose key |
| 519 | |
| 520 | DEC terminals have a Compose key, which provides an easy-to-remember |
| 521 | way of typing accented characters. You press Compose and then type |
| 522 | two more characters. The two characters are \q{combined} to produce |
| 523 | an accented character. The choices of character are designed to be |
| 524 | easy to remember; for example, composing \q{e} and \q{`} produces |
| 525 | the \q{\u00e8{e-grave}} character. |
| 526 | |
| 527 | If you enable the \q{Application and AltGr act as Compose key} |
| 528 | option, the Windows Application key and the AltGr key will both have |
| 529 | this behaviour. |
| 530 | |
| 531 | \S{config-ctrlalt} \q{Control-Alt is different from AltGr} |
| 532 | |
| 533 | Some old keyboards do not have an AltGr key, which can make it |
| 534 | difficult to type some characters. PuTTY can be configured to treat |
| 535 | the key combination Ctrl + Left Alt the same way as the AltGr key. |
| 536 | |
| 537 | By default, this checkbox is checked, and the key combination Ctrl + |
| 538 | Left Alt does something completely different. PuTTY's usual handling |
| 539 | of the left Alt key is to prefix the Escape (Control-\cw{[}) |
| 540 | character to whatever character sequence the rest of the keypress |
| 541 | would generate. For example, Alt-A generates Escape followed by |
| 542 | \c{a}. So Alt-Ctrl-A would generate Escape, followed by Control-A. |
| 543 | |
| 544 | If you uncheck this box, Ctrl-Alt will become a synonym for AltGr, |
| 545 | so you can use it to type extra graphic characters if your keyboard |
| 546 | has any. |
| 547 | |
| 548 | \H{config-window} The Window panel |
| 549 | |
| 550 | The Window configuration panel allows you to control aspects of the |
| 551 | PuTTY window and its behaviour. |
| 552 | |
| 553 | \S{config-winsize} Setting the size of the PuTTY window |
| 554 | |
| 555 | The \e{Rows} and \e{Columns} boxes let you set the PuTTY window to a |
| 556 | precise size. Of course you can also drag the window to a new size |
| 557 | while a session is running. |
| 558 | |
| 559 | \S{config-winsizelock} Locking the size of the PuTTY window |
| 560 | |
| 561 | These options allow you to control what happens when the user tries |
| 562 | to resize the PuTTY window. |
| 563 | |
| 564 | When you resize the PuTTY window, one of three things can happen: |
| 565 | |
| 566 | \b Nothing (if you have completely disabled resizes). |
| 567 | |
| 568 | \b The font size can stay the same and the number of rows and |
| 569 | columns in the terminal can change. |
| 570 | |
| 571 | \b The number of rows and columns in the terminal can stay the same, |
| 572 | and the font size can change. |
| 573 | |
| 574 | You can control which of these happens using the \q{Lock terminal |
| 575 | size against resizing} and \q{Lock font size against resizing} |
| 576 | options. If you lock both, the window will refuse to be resized at |
| 577 | all. If you lock just the terminal size, the font size will change |
| 578 | when you resize the window. If you lock just the font size, the |
| 579 | terminal size will change when you resize the window. |
| 580 | |
| 581 | \S{config-scrollback} Controlling scrollback |
| 582 | |
| 583 | Text that scrolls off the top of the PuTTY terminal window is kept |
| 584 | for reference. The scrollbar on the right of the window lets you |
| 585 | view the scrolled-off text. You can also page through the scrollback |
| 586 | using the keyboard, by pressing Shift-PgUp and Shift-PgDn. |
| 587 | |
| 588 | The \q{Lines of scrollback} box lets you configure how many lines of |
| 589 | text PuTTY keeps. The \q{Display scrollbar} option allows you to |
| 590 | hide the scrollbar (although you can still view the scrollback using |
| 591 | Shift-PgUp and Shift-PgDn). |
| 592 | |
| 593 | If you are viewing part of the scrollback when the server sends more |
| 594 | text to PuTTY, the screen will revert to showing the current |
| 595 | terminal contents. You can disable this behaviour by turning off |
| 596 | \q{Reset scrollback on display activity}. You can also make the |
| 597 | screen revert when you press a key, by turning on \q{Reset |
| 598 | scrollback on keypress}. |
| 599 | |
| 600 | \S{config-warnonclose} \q{Warn before closing window} |
| 601 | |
| 602 | If you press the Close button in a PuTTY window that contains a |
| 603 | running session, PuTTY will put up a warning window asking if you |
| 604 | really meant to close the window. A window whose session has already |
| 605 | terminated can always be closed without a warning. |
| 606 | |
| 607 | If you want to be able to close a window quickly, you can disable |
| 608 | the \q{Warn before closing window} option. |
| 609 | |
| 610 | \S{config-altf4} \q{Window closes on ALT-F4} |
| 611 | |
| 612 | By default, pressing ALT-F4 causes the window to close (or a warning |
| 613 | box to appear; see \k{config-warnonclose}). If you disable the |
| 614 | \q{Window closes on ALT-F4} option, then pressing ALT-F4 will simply |
| 615 | send a key sequence to the server. |
| 616 | |
| 617 | \S{config-altspace} \q{System menu appears on ALT-Space} |
| 618 | |
| 619 | If this option is enabled, then pressing ALT-Space will bring up the |
| 620 | PuTTY window's menu, like clicking on the top left corner. If it is |
| 621 | disabled, then pressing ALT-Space will just send \c{ESC SPACE} to |
| 622 | the server. |
| 623 | |
| 624 | Some accessibility programs for Windows may need this option |
| 625 | enabling to be able to control PuTTY's window successfully. For |
| 626 | instance, Dragon NaturallySpeaking requires it both to open the |
| 627 | system menu via voice, and to close, minimise, maximise and restore |
| 628 | the window. |
| 629 | |
| 630 | \S{config-altonly} \q{System menu appears on Alt alone} |
| 631 | |
| 632 | If this option is enabled, then pressing and releasing ALT will |
| 633 | bring up the PuTTY window's menu, like clicking on the top left |
| 634 | corner. If it is disabled, then pressing and releasing ALT will have |
| 635 | no effect. |
| 636 | |
| 637 | \S{config-alwaysontop} \q{Ensure window is always on top} |
| 638 | |
| 639 | If this option is enabled, the PuTTY window will stay on top of all |
| 640 | other windows. |
| 641 | |
| 642 | \S{config-fullscreen} \q{Full screen on Alt-Enter} |
| 643 | |
| 644 | If this option is enabled, then pressing Alt-Enter will cause the |
| 645 | PuTTY window to become full-screen - that is, it will not only |
| 646 | maximise itself, it will expand so that the title bar goes off the |
| 647 | top of the screen, and place itself on top of the Windows taskbar, |
| 648 | so that \e{nothing} is visible on the screen except PuTTY. Pressing |
| 649 | Alt-Enter again will restore the previous window size. |
| 650 | |
| 651 | \H{config-appearance} The Appearance panel |
| 652 | |
| 653 | The Appearance configuration panel allows you to control aspects of |
| 654 | PuTTY's appearance. |
| 655 | |
| 656 | \S{config-cursor} Controlling the appearance of the cursor |
| 657 | |
| 658 | The \q{Cursor appearance} option lets you configure the cursor to be |
| 659 | a block, an underline, or a vertical line. A block cursor becomes an |
| 660 | empty box when the window loses focus; an underline or a vertical |
| 661 | line becomes dotted. |
| 662 | |
| 663 | The \q{Cursor blinks} option makes the cursor blink on and off. This |
| 664 | works in any of the cursor modes. |
| 665 | |
| 666 | \S{config-font} Controlling the font used in the terminal window |
| 667 | |
| 668 | This option allows you to choose what font, in what size, the PuTTY |
| 669 | terminal window uses to display the text in the session. You will be |
| 670 | offered a choice from all the fixed-width fonts installed on the |
| 671 | system. (VT100-style terminal handling can only deal with fixed- |
| 672 | width fonts.) |
| 673 | |
| 674 | \S{config-title} Controlling the window title |
| 675 | |
| 676 | The \q{Window title} edit box allows you to set the title of the |
| 677 | PuTTY window. By default the window title will contain the host name |
| 678 | followed by \q{PuTTY}, for example \c{server1.example.com - PuTTY}. |
| 679 | If you want a different window title, this is where to set it. |
| 680 | |
| 681 | PuTTY allows the server to send \c{xterm} control sequences which |
| 682 | modify the title of the window in mid-session. There is also an |
| 683 | \c{xterm} sequence to modify the title of the window's \e{icon}. |
| 684 | This makes sense in a windowing system where the window becomes an |
| 685 | icon when minimised, such as Windows 3.1 or most X Window System |
| 686 | setups; but in the Windows 95-like user interface it isn't as |
| 687 | applicable. By default PuTTY's window title and Taskbar caption will |
| 688 | change into the server-supplied icon title if you minimise the PuTTY |
| 689 | window, and change back to the server-supplied window title if you |
| 690 | restore it. (If the server has not bothered to supply a window or |
| 691 | icon title, none of this will happen.) By checking the box marked |
| 692 | \q{Avoid ever using icon title}, you can arrange that PuTTY will |
| 693 | always display the window title, and completely ignore any icon |
| 694 | titles the server sends it. |
| 695 | |
| 696 | \S{config-mouseptr} \q{Hide mouse pointer when typing in window} |
| 697 | |
| 698 | If you enable this option, the mouse pointer will disappear if the |
| 699 | PuTTY window is selected and you press a key. This way, it will not |
| 700 | obscure any of the text in the window while you work in your |
| 701 | session. As soon as you move the mouse, the pointer will reappear. |
| 702 | |
| 703 | This option is disabled by default, so the mouse pointer remains |
| 704 | visible at all times. |
| 705 | |
| 706 | \S{config-winborder} Controlling the window border |
| 707 | |
| 708 | PuTTY allows you to configure the appearance of the window border to |
| 709 | some extent. |
| 710 | |
| 711 | The checkbox marked \q{Sunken-edge border} changes the appearance of |
| 712 | the window border to something more like a DOS box: the inside edge |
| 713 | of the border is highlighted as if it sank down to meet the surface |
| 714 | inside the window. This makes the border a little bit thicker as |
| 715 | well. It's hard to describe well. Try it and see if you like it. |
| 716 | |
| 717 | You can also configure a completely blank gap between the text in |
| 718 | the window and the border, using the \q{Gap between text and window |
| 719 | edge} control. By default this is set at one pixel. You can reduce |
| 720 | it to zero, or increase it further. |
| 721 | |
| 722 | \H{config-translation} The Translation panel |
| 723 | |
| 724 | The Translation configuration panel allows you to control the |
| 725 | translation between the character set understood by the server and |
| 726 | the character set understood by PuTTY. |
| 727 | |
| 728 | \S{config-charset} Controlling character set translation |
| 729 | |
| 730 | During an interactive session, PuTTY receives a stream of 8-bit |
| 731 | bytes from the server, and in order to display them on the screen it |
| 732 | needs to know what character set to interpret them in. |
| 733 | |
| 734 | There are a lot of character sets to choose from. The \q{Received |
| 735 | data assumed to be in which character set} option lets you select |
| 736 | one. By default PuTTY will attempt to choose a character set that is |
| 737 | right for your locale as reported by Windows; if it gets it wrong, |
| 738 | you can select a different one using this control. |
| 739 | |
| 740 | A few notable character sets are: |
| 741 | |
| 742 | \b The ISO-8859 series are all standard character sets that include |
| 743 | various accented characters appropriate for different sets of |
| 744 | languages. |
| 745 | |
| 746 | \b The Win125x series are defined by Microsoft, for similar |
| 747 | purposes. In particular Win1252 is almost equivalent to ISO-8859-1, |
| 748 | but contains a few extra characters such as matched quotes and the |
| 749 | Euro symbol. |
| 750 | |
| 751 | \b If you want the old IBM PC character set with block graphics and |
| 752 | line-drawing characters, you can select \q{CP437}. |
| 753 | |
| 754 | \b PuTTY also supports Unicode mode, in which the data coming from |
| 755 | the server is interpreted as being in the UTF-8 encoding of Unicode. |
| 756 | If you select \q{UTF-8} as a character set you can use this mode. |
| 757 | Not all server-side applications will support it. |
| 758 | |
| 759 | \S{config-cyr} \q{Caps Lock acts as Cyrillic switch} |
| 760 | |
| 761 | This feature allows you to switch between a US/UK keyboard layout |
| 762 | and a Cyrillic keyboard layout by using the Caps Lock key, if you |
| 763 | need to type (for example) Russian and English side by side in the |
| 764 | same document. |
| 765 | |
| 766 | Currently this feature is not expected to work properly if your |
| 767 | native keyboard layout is not US or UK. |
| 768 | |
| 769 | \S{config-linedraw} Controlling display of line drawing characters |
| 770 | |
| 771 | VT100-series terminals allow the server to send control sequences |
| 772 | that shift temporarily into a separate character set for drawing |
| 773 | lines and boxes. PuTTY has a variety of ways to support this |
| 774 | capability. In general you should probably try lots of options until |
| 775 | you find one that your particular font supports. |
| 776 | |
| 777 | \b \q{Font has XWindows encoding} is for use with fonts that have a |
| 778 | special encoding, where the lowest 32 character positions (below the |
| 779 | ASCII printable range) contain the line-drawing characters. This is |
| 780 | unlikely to be the case with any standard Windows font; it will |
| 781 | probably only apply to custom-built fonts or fonts that have been |
| 782 | automatically converted from the X Window System. |
| 783 | |
| 784 | \b \q{Use font in both ANSI and OEM modes} tries to use the same |
| 785 | font in two different character sets, to obtain a wider range of |
| 786 | characters. This doesn't always work; some fonts claim to be a |
| 787 | different size depending on which character set you try to use. |
| 788 | |
| 789 | \b \q{Use font in OEM mode only} is more reliable than that, but can |
| 790 | miss out other characters from the main character set. |
| 791 | |
| 792 | \b \q{Poor man's line drawing} assumes that the font \e{cannot} |
| 793 | generate the line and box characters at all, so it will use the |
| 794 | \c{+}, \c{-} and \c{|} characters to draw approximations to boxes. |
| 795 | You should use this option if none of the other options works. |
| 796 | |
| 797 | \b \q{Unicode mode} tries to use the box characters that are present |
| 798 | in Unicode. For good Unicode-supporting fonts this is probably the |
| 799 | most reliable and functional option. |
| 800 | |
| 801 | \H{config-selection} The Selection panel |
| 802 | |
| 803 | The Selection panel allows you to control the way copy and paste |
| 804 | work in the PuTTY window. |
| 805 | |
| 806 | \S{config-linedrawpaste} Controlling the pasting of line drawing |
| 807 | characters |
| 808 | |
| 809 | By default, when you copy and paste a piece of the PuTTY screen that |
| 810 | contains VT100 line and box drawing characters, PuTTY will translate |
| 811 | them into the \q{poor man's} line-drawing characters \c{+}, \c{-} |
| 812 | and \c{|}. The checkbox \q{Don't translate line drawing chars} |
| 813 | disables this feature, so line-drawing characters will be pasted as |
| 814 | if they were in the normal character set. This will typically mean |
| 815 | they come out mostly as \c{q} and \c{x}, with a scattering of |
| 816 | \c{jklmntuvw} at the corners. This might be useful if you were |
| 817 | trying to recreate the same box layout in another program, for |
| 818 | example. |
| 819 | |
| 820 | \S{config-mouse} Changing the actions of the mouse buttons |
| 821 | |
| 822 | PuTTY's copy and paste mechanism is modelled on the Unix \c{xterm} |
| 823 | application. The X Window System uses a three-button mouse, and the |
| 824 | convention is that the left button selects, the right button extends |
| 825 | an existing selection, and the middle button pastes. |
| 826 | |
| 827 | Windows typically only has two mouse buttons, so in PuTTY's default |
| 828 | configuration, the \e{right} button pastes, and the \e{middle} |
| 829 | button (if you have one) extends a selection. |
| 830 | |
| 831 | If you have a three-button mouse and you are already used to the |
| 832 | \c{xterm} arrangement, you can select it using the \q{Action of |
| 833 | mouse buttons} control. |
| 834 | |
| 835 | \S{config-mouseshift} \q{Shift overrides application's use of mouse} |
| 836 | |
| 837 | PuTTY allows the server to send control codes that let it take over |
| 838 | the mouse and use it for purposes other than copy and paste. |
| 839 | Applications which use this feature include the text-mode web |
| 840 | browser \c{links}, the Usenet newsreader \c{trn} version 4, and the |
| 841 | file manager \c{mc} (Midnight Commander). |
| 842 | |
| 843 | When running one of these applications, pressing the mouse buttons |
| 844 | no longer performs copy and paste. If you do need to copy and paste, |
| 845 | you can still do so if you hold down Shift while you do your mouse |
| 846 | clicks. |
| 847 | |
| 848 | However, it is possible in theory for applications to even detect |
| 849 | and make use of Shift + mouse clicks. We don't know of any |
| 850 | applications that do this, but in case someone ever writes one, |
| 851 | unchecking the \q{Shift overrides application's use of mouse} |
| 852 | checkbox will cause Shift + mouse clicks to go to the server as well |
| 853 | (so that mouse-driven copy and paste will be completely disabled). |
| 854 | |
| 855 | \S{config-charclasses} Configuring word-by-word selection |
| 856 | |
| 857 | PuTTY will select a word at a time in the terminal window if you |
| 858 | double-click to begin the drag. This panel allows you to control |
| 859 | precisely what is considered to be a word. |
| 860 | |
| 861 | Each character is given a \e{class}, which is a small number |
| 862 | (typically 0, 1 or 2). PuTTY considers a single word to be any |
| 863 | number of adjacent characters in the same class. So by modifying the |
| 864 | assignment of characters to classes, you can modify the word-by-word |
| 865 | selection behaviour. |
| 866 | |
| 867 | In the default configuration, the character classes are: |
| 868 | |
| 869 | \b Class 0 contains white space and control characters. |
| 870 | |
| 871 | \b Class 1 contains most punctuation. |
| 872 | |
| 873 | \b Class 2 contains letters, numbers and a few pieces of punctuation |
| 874 | (the double quote, minus sign, period, forward slash and |
| 875 | underscore). |
| 876 | |
| 877 | So, for example, if you assign the \c{@} symbol into character class |
| 878 | 2, you will be able to select an e-mail address with just a double |
| 879 | click. |
| 880 | |
| 881 | In order to adjust these assignments, you start by selecting a group |
| 882 | of characters in the list box. Then enter a class number in the edit |
| 883 | box below, and press the \q{Set} button. |
| 884 | |
| 885 | This mechanism currently only covers ASCII characters, because it |
| 886 | isn't feasible to expand the list to cover the whole of Unicode. |
| 887 | |
| 888 | \H{config-colours} The Colours panel |
| 889 | |
| 890 | The Colours panel allows you to control PuTTY's use of colour. |
| 891 | |
| 892 | \S{config-boldcolour} \q{Bolded text is a different colour} |
| 893 | |
| 894 | When the server sends a control sequence indicating that some text |
| 895 | should be displayed in bold, PuTTY can handle this two ways. It can |
| 896 | either change the font for a bold version, or use the same font in a |
| 897 | brighter colour. This control lets you choose which. |
| 898 | |
| 899 | By default the box is checked, so non-bold text is displayed in |
| 900 | light grey and bold text is displayed in bright white (and similarly |
| 901 | in other colours). If you uncheck the box, bold and non-bold text |
| 902 | will be displayed in the same colour, and instead the font will |
| 903 | change to indicate the difference. |
| 904 | |
| 905 | \S{config-logpalette} \q{Attempt to use logical palettes} |
| 906 | |
| 907 | Logical palettes are a mechanism by which a Windows application |
| 908 | running on an 8-bit colour display can select precisely the colours |
| 909 | it wants instead of going with the Windows standard defaults. |
| 910 | |
| 911 | If you are not getting the colours you ask for on an 8-bit display, |
| 912 | you can try enabling this option. However, be warned that it's never |
| 913 | worked very well. |
| 914 | |
| 915 | \S{config-colourcfg} Adjusting the colours in the terminal window |
| 916 | |
| 917 | The main colour control allows you to specify exactly what colours |
| 918 | things should be displayed in. To modify one of the PuTTY colours, |
| 919 | use the list box to select which colour you want to modify. The RGB |
| 920 | values for that colour will appear on the right-hand side of the |
| 921 | list box. Now, if you press the \q{Modify} button, you will be |
| 922 | presented with a colour selector, in which you can choose a new |
| 923 | colour to go in place of the old one. |
| 924 | |
| 925 | PuTTY allows you to set the cursor colour, the default foreground |
| 926 | and background, and the precise shades of all the ANSI configurable |
| 927 | colours (black, red, green, yellow, blue, magenta, cyan, and white). |
| 928 | In addition, if you have selected \q{Bolded text is a different |
| 929 | colour}, you can also modify the precise shades used for the bold |
| 930 | versions of these colours. |
| 931 | |
| 932 | \H{config-connection} The Connection panel |
| 933 | |
| 934 | The Connection panel allows you to configure options that apply to |
| 935 | more than one type of connection. |
| 936 | |
| 937 | \S{config-termtype} \q{Terminal-type string} |
| 938 | |
| 939 | Most servers you might connect to with PuTTY are designed to be |
| 940 | connected to from lots of different types of terminal. In order to |
| 941 | send the right control sequences to each one, the server will need |
| 942 | to know what type of terminal it is dealing with. Therefore, each of |
| 943 | the SSH, Telnet and Rlogin protocols allow a text string to be sent |
| 944 | down the connection describing the terminal. |
| 945 | |
| 946 | PuTTY attempts to emulate the Unix \c{xterm} program, and by default |
| 947 | it reflects this by sending \c{xterm} as a terminal-type string. If |
| 948 | you find this is not doing what you want - perhaps the remote |
| 949 | terminal reports \q{Unknown terminal type} - you could try setting |
| 950 | this to something different, such as \c{vt220}. |
| 951 | |
| 952 | If you're not sure whether a problem is due to the terminal type |
| 953 | setting or not, you probably need to consult the manual for your |
| 954 | application or your server. |
| 955 | |
| 956 | \S{config-username} \q{Auto-login username} |
| 957 | |
| 958 | All three of the SSH, Telnet and Rlogin protocols allow you to |
| 959 | specify what user name you want to log in as, without having to type |
| 960 | it explicitly every time. (Some Telnet servers don't support this.) |
| 961 | |
| 962 | In this box you can type that user name. |
| 963 | |
| 964 | \S{config-keepalive} Using keepalives to prevent disconnection |
| 965 | |
| 966 | If you find your sessions are closing unexpectedly (\q{Connection |
| 967 | reset by peer}) after they have been idle for a while, you might |
| 968 | want to try using this option. |
| 969 | |
| 970 | Some network routers and firewalls need to keep track of all |
| 971 | connections through them. Usually, these firewalls will assume a |
| 972 | connection is dead if no data is transferred in either direction |
| 973 | after a certain time interval. This can cause PuTTY sessions to be |
| 974 | unexpectedly closed by the firewall if no traffic is seen in the |
| 975 | session for some time. |
| 976 | |
| 977 | The keepalive option (\q{Seconds between keepalives}) allows you to |
| 978 | configure PuTTY to send data through the session at regular |
| 979 | intervals, in a way that does not disrupt the actual terminal |
| 980 | session. If you find your firewall is cutting idle connections off, |
| 981 | you can try entering a non-zero value in this field. The value is |
| 982 | measured in seconds; so, for example, if your firewall cuts |
| 983 | connections off after ten minutes then you might want to enter 300 |
| 984 | seconds (5 minutes) in the box. |
| 985 | |
| 986 | Note that keepalives are not always helpful. They help if you have a |
| 987 | firewall which drops your connection after an idle period; but if |
| 988 | the network between you and the server suffers from breaks in |
| 989 | connectivity then keepalives can actually make things worse. If a |
| 990 | session is idle, and connectivity is temporarily lost between the |
| 991 | endpoints, but the connectivity is restored before either side tries |
| 992 | to send anything, then there will be no problem - neither endpoint |
| 993 | will notice that anything was wrong. However, if one side does send |
| 994 | something during the break, it will repeatedly try to re-send, and |
| 995 | eventually give up and abandon the connection. Then when |
| 996 | connectivity is restored, the other side will find that the first |
| 997 | side doesn't believe there is an open connection any more. |
| 998 | Keepalives can make this sort of problem worse, because they |
| 999 | increase the probability that PuTTY will attempt to send data during |
| 1000 | a break in connectivity. Therefore, you might find they help |
| 1001 | connection loss, or you might find they make it worse, depending on |
| 1002 | what \e{kind} of network problems you have between you and the |
| 1003 | server. |
| 1004 | |
| 1005 | Keepalives are only supported in Telnet and SSH; the Rlogin and Raw |
| 1006 | protocols offer no way of implementing them. |
| 1007 | |
| 1008 | \H{config-telnet} The Telnet panel |
| 1009 | |
| 1010 | The Telnet panel allows you to configure options that only apply to |
| 1011 | Telnet sessions. |
| 1012 | |
| 1013 | \S{config-termspeed} \q{Terminal-speed string} |
| 1014 | |
| 1015 | Telnet allows the client to send a text string that describes the |
| 1016 | terminal speed. PuTTY lets you configure this, in case you find the |
| 1017 | server is reacting badly to the default value. (I'm not aware of any |
| 1018 | servers that do have a problem with it.) |
| 1019 | |
| 1020 | \S{config-environ} Setting environment variables on the server |
| 1021 | |
| 1022 | The Telnet protocol also provides a means for the client to pass |
| 1023 | environment variables to the server. Many Telnet servers have |
| 1024 | stopped supporting this feature due to security flaws, but PuTTY |
| 1025 | still supports it for the benefit of any servers which have found |
| 1026 | other ways around the security problems than just disabling the |
| 1027 | whole mechanism. |
| 1028 | |
| 1029 | To add an environment variable to the list transmitted down the |
| 1030 | connection, you enter the variable name in the \q{Variable} box, |
| 1031 | enter its value in the \q{Value} box, and press the \q{Add} button. |
| 1032 | To remove one from the list, select it in the list box and press |
| 1033 | \q{Remove}. |
| 1034 | |
| 1035 | \S{config-oldenviron} \q{Handling of OLD_ENVIRON ambiguity} |
| 1036 | |
| 1037 | The original Telnet mechanism for passing environment variables was |
| 1038 | badly specified. At the time the standard (RFC 1408) was written, |
| 1039 | BSD telnet implementations were already supporting the feature, and |
| 1040 | the intention of the standard was to describe the behaviour the BSD |
| 1041 | implementations were already using. |
| 1042 | |
| 1043 | Sadly there was a typing error in the standard when it was issued, |
| 1044 | and two vital function codes were specified the wrong way round. BSD |
| 1045 | implementations did not change, and the standard was not corrected. |
| 1046 | Therefore, it's possible you might find either BSD or RFC-compliant |
| 1047 | implementations out there. This switch allows you to choose which |
| 1048 | one PuTTY claims to be. |
| 1049 | |
| 1050 | The problem was solved by issuing a second standard, defining a new |
| 1051 | Telnet mechanism called \cw{NEW_ENVIRON}, which behaved exactly like |
| 1052 | the original \cw{OLD_ENVIRON} but was not encumbered by existing |
| 1053 | implementations. Most Telnet servers now support this, and it's |
| 1054 | unambiguous. This feature should only be needed if you have trouble |
| 1055 | passing environment variables to quite an old server. |
| 1056 | |
| 1057 | \S{config-ptelnet} Passive and active Telnet negotiation modes |
| 1058 | |
| 1059 | In a Telnet connection, there are two types of data passed between |
| 1060 | the client and the server: actual text, and \e{negotiations} about |
| 1061 | which Telnet extra features to use. |
| 1062 | |
| 1063 | PuTTY can use two different strategies for negotiation: |
| 1064 | |
| 1065 | \b In \e{active} mode, PuTTY starts to send negotiations as soon as |
| 1066 | the connection is opened. |
| 1067 | |
| 1068 | \b In \e{passive} mode, PuTTY will wait to negotiate until it sees a |
| 1069 | negotiation from the server. |
| 1070 | |
| 1071 | The obvious disadvantage of passive mode is that if the server is |
| 1072 | also operating in a passive mode, then negotiation will never begin |
| 1073 | at all. For this reason PuTTY defaults to active mode. |
| 1074 | |
| 1075 | However, sometimes passive mode is required in order to successfully |
| 1076 | get through certain types of firewall and Telnet proxy server. If |
| 1077 | you have confusing trouble with a firewall, you could try enabling |
| 1078 | passive mode to see if it helps. |
| 1079 | |
| 1080 | \S{config-telnetkey} \q{Keyboard sends telnet Backspace and Interrupt} |
| 1081 | |
| 1082 | If this box is checked, the Backspace key on the keyboard will send |
| 1083 | the Telnet special backspace code, and Control-C will send the |
| 1084 | Telnet special interrupt code. You probably shouldn't enable this |
| 1085 | unless you know what you're doing. |
| 1086 | |
| 1087 | \H{config-rlogin} The Rlogin panel |
| 1088 | |
| 1089 | The Rlogin panel allows you to configure options that only apply to |
| 1090 | Rlogin sessions. |
| 1091 | |
| 1092 | \S{config-rlogin-termspeed} \q{Terminal-speed string} |
| 1093 | |
| 1094 | Like Telnet, Rlogin allows the client to send a text string that |
| 1095 | describes the terminal speed. PuTTY lets you configure this, in case |
| 1096 | you find the server is reacting badly to the default value. (I'm not |
| 1097 | aware of any servers that do have a problem with it.) |
| 1098 | |
| 1099 | \S{config-rlogin-localuser} \q{Local username} |
| 1100 | |
| 1101 | Rlogin allows an automated (password-free) form of login by means of |
| 1102 | a file called \c{.rhosts} on the server. You put a line in your |
| 1103 | \c{.rhosts} file saying something like \c{jbloggs@pc1.example.com}, |
| 1104 | and then when you make an Rlogin connection the client transmits the |
| 1105 | username of the user running the Rlogin client. The server checks |
| 1106 | the username and hostname against \c{.rhosts}, and if they match it |
| 1107 | does not ask for a password. |
| 1108 | |
| 1109 | This only works because Unix systems contain a safeguard to stop a |
| 1110 | user from pretending to be another user in an Rlogin connection. |
| 1111 | Rlogin connections have to come from port numbers below 1024, and |
| 1112 | Unix systems prohibit this to unprivileged processes; so when the |
| 1113 | server sees a connection from a low-numbered port, it assumes the |
| 1114 | client end of the connection is held by a privileged (and therefore |
| 1115 | trusted) process, so it believes the claim of who the user is. |
| 1116 | |
| 1117 | Windows does not have this restriction: \e{any} user can initiate an |
| 1118 | outgoing connection from a low-numbered port. Hence, the Rlogin |
| 1119 | \c{.rhosts} mechanism is completely useless for securely |
| 1120 | distinguishing several different users on a Windows machine. If you |
| 1121 | have a \c{.rhosts} entry pointing at a Windows PC, you should assume |
| 1122 | that \e{anyone} using that PC can spoof your username in an Rlogin |
| 1123 | connection and access your account on the server. |
| 1124 | |
| 1125 | The \q{Local username} control allows you to specify what user name |
| 1126 | PuTTY should claim you have, in case it doesn't match your Windows |
| 1127 | user name (or in case you didn't bother to set up a Windows user |
| 1128 | name). |
| 1129 | |
| 1130 | \H{config-ssh} The SSH panel |
| 1131 | |
| 1132 | The SSH panel allows you to configure options that only apply to |
| 1133 | SSH sessions. |
| 1134 | |
| 1135 | \S{config-command} Executing a specific command on the server |
| 1136 | |
| 1137 | In SSH, you don't have to run a general shell session on the server. |
| 1138 | Instead, you can choose to run a single specific command (such as a |
| 1139 | mail user agent, for example). If you want to do this, enter the |
| 1140 | command in the \q{Remote command} box. |
| 1141 | |
| 1142 | \S{config-ssh-pty} \q{Don't allocate a pseudo-terminal} |
| 1143 | |
| 1144 | When connecting to a Unix system, most interactive shell sessions |
| 1145 | are run in a \e{pseudo-terminal}, which allows the Unix system to |
| 1146 | pretend it's talking to a real physical terminal device but allows |
| 1147 | the SSH server to catch all the data coming from that fake device |
| 1148 | and send it back to the client. |
| 1149 | |
| 1150 | Occasionally you might find you have a need to run a session \e{not} |
| 1151 | in a pseudo-terminal. In PuTTY, this is generally only useful for |
| 1152 | very specialist purposes; although in Plink (see \k{plink}) it is |
| 1153 | the usual way of working. |
| 1154 | |
| 1155 | \S{config-ssh-comp} \q{Enable compression} |
| 1156 | |
| 1157 | This enables data compression in the SSH connection: data sent by |
| 1158 | the server is compressed before sending, and decompressed at the |
| 1159 | client end. Likewise, data sent by PuTTY to the server is compressed |
| 1160 | first and the server decompresses it at the other end. This can help |
| 1161 | make the most of a low-bandwidth connection. |
| 1162 | |
| 1163 | \S{config-ssh-prot} \q{Preferred SSH protocol version} |
| 1164 | |
| 1165 | This allows you to select whether you would like to use SSH protocol |
| 1166 | version 1 or version 2. \#{FIXME: say something about this elsewhere?} |
| 1167 | |
| 1168 | PuTTY will attempt to use protocol 1 if the server you connect to |
| 1169 | does not offer protocol 2, and vice versa. |
| 1170 | |
| 1171 | \S{config-ssh-macbug} \q{Imitate SSH 2 MAC bug} |
| 1172 | |
| 1173 | This option \e{should} now be unnecessary. It existed in order to |
| 1174 | work around a bug in early versions (2.3.0 and below) of the SSH |
| 1175 | server software from \cw{ssh.com}. The symptom of this problem would |
| 1176 | be that PuTTY would die unexpectedly at the beginning of the |
| 1177 | session, saying \q{Incorrect MAC received on packet}. |
| 1178 | |
| 1179 | Current versions of PuTTY attempt to detect these faulty servers and |
| 1180 | enable the bug compatibility automatically, so you should never need |
| 1181 | to use this option any more. |
| 1182 | |
| 1183 | \S{config-ssh-encryption} Encryption algorithm selection |
| 1184 | |
| 1185 | PuTTY supports a variety of different encryption algorithms, and |
| 1186 | allows you to choose which one you prefer to use. You can do this by |
| 1187 | dragging the algorithms up and down in the list box to specify a |
| 1188 | preference order. When you make an SSH connection, PuTTY will search |
| 1189 | down the list from the top until it finds an algorithm supported by |
| 1190 | the server, and then use that. |
| 1191 | |
| 1192 | If the algorithm PuTTY finds is below the \q{warn below here} line, |
| 1193 | you will see a warning box when you make the connection: |
| 1194 | |
| 1195 | \c The first cipher supported by the server |
| 1196 | \c is single-DES, which is below the configured |
| 1197 | \c warning threshold. |
| 1198 | \c Do you want to continue with this connection? |
| 1199 | |
| 1200 | This warns you that the first available encryption is not a very |
| 1201 | secure one. Typically you would put the \q{warn below here} line |
| 1202 | between the encryptions you consider secure and the ones you |
| 1203 | consider substandard. |
| 1204 | |
| 1205 | By default, PuTTY supplies a preference order intended to reflect a |
| 1206 | reasonable preference in terms of security and speed. |
| 1207 | |
| 1208 | \H{config-ssh-auth} The Auth panel |
| 1209 | |
| 1210 | The Auth panel allows you to configure authentication options for |
| 1211 | SSH sessions. |
| 1212 | |
| 1213 | \S{config-ssh-tis} \q{Attempt TIS or CryptoCard authentication} |
| 1214 | |
| 1215 | TIS and CryptoCard authentication are simple challenge/response |
| 1216 | forms of authentication available in SSH protocol version 1 only. |
| 1217 | You might use them if you were using S/Key one-time passwords, for |
| 1218 | example, or if you had a physical security token that generated |
| 1219 | responses to authentication challenges. |
| 1220 | |
| 1221 | With this switch enabled, PuTTY will attempt these forms of |
| 1222 | authentication if the server is willing to try them. You will be |
| 1223 | presented with a challenge string (which will be different every |
| 1224 | time) and must supply the correct response in order to log in. If |
| 1225 | your server supports this, you should talk to your system |
| 1226 | administrator about precisely what form these challenges and |
| 1227 | responses take. |
| 1228 | |
| 1229 | \S{config-ssh-agentfwd} \q{Allow agent forwarding} |
| 1230 | |
| 1231 | This option allows the SSH server to open forwarded connections back |
| 1232 | to your local copy of Pageant. If you are not running Pageant, this |
| 1233 | option will do nothing. |
| 1234 | |
| 1235 | See \k{pageant} for general information on Pageant, and |
| 1236 | \k{pageant-forward} for information on agent forwarding. Note that |
| 1237 | there is a security risk involved with enabling this option; see |
| 1238 | \k{pageant-security} for details. |
| 1239 | |
| 1240 | \S{config-ssh-privkey} \q{Private key file for authentication} |
| 1241 | |
| 1242 | This box is where you enter the name of your private key file if you |
| 1243 | are using public key authentication. See \k{pubkey} for information |
| 1244 | about public key authentication in SSH. |
| 1245 | |
| 1246 | \H{config-ssh-tunnels} The Tunnels panel |
| 1247 | |
| 1248 | The Tunnels panel allows you to configure tunnelling of other |
| 1249 | connection types through an SSH connection. |
| 1250 | |
| 1251 | \S{config-ssh-x11} X11 forwarding |
| 1252 | |
| 1253 | If your server lets you run X Window System applications, X11 |
| 1254 | forwarding allows you to securely give those applications access to |
| 1255 | a local X display on your PC. |
| 1256 | |
| 1257 | This feature will only be useful if you have an X server on your PC, |
| 1258 | such as Exceed or XWin32. |
| 1259 | |
| 1260 | To enable X11 forwarding, check the \q{Enable X11 forwarding} box. |
| 1261 | If your X display is not the primary display on your local machine |
| 1262 | (which it almost certainly will be unless you have deliberately |
| 1263 | arranged otherwise), you need to enter its location in the \q{X |
| 1264 | display location} box. |
| 1265 | |
| 1266 | \# FIXME: perhaps link to some more general X forwarding info? |
| 1267 | |
| 1268 | \S{config-ssh-portfwd} Port forwarding |
| 1269 | |
| 1270 | Port forwarding allows you to tunnel other types of network |
| 1271 | connection down an SSH connection. |
| 1272 | |
| 1273 | To set up a local port forwarding, make sure the \q{Local} radio |
| 1274 | button is set. Then enter a local port number (on your PC) in the |
| 1275 | \q{Source port} box, and a hostname and port number (separated by a |
| 1276 | colon) in the \q{Destination} box, and finally press the \q{Add} |
| 1277 | button. For example, you might select a source port of 10079, and a |
| 1278 | destination of \c{server2.example.com:79}. |
| 1279 | |
| 1280 | If you do this, and then start the session, you should find that |
| 1281 | connecting to your local PC on port 10079 gives you a connection to |
| 1282 | port 79 (the finger server) on \c{server2.example.com}. The |
| 1283 | connection is actually going to PuTTY itself, which encrypts the |
| 1284 | connection data and sends it down the secure channel to the SSH |
| 1285 | server. The connection then proceeds in clear from there to the |
| 1286 | eventual destination. So you might use this (for example) to forward |
| 1287 | a connection between two non-hostile network zones that are only |
| 1288 | connected by a hostile zone such as the open Internet. |
| 1289 | |
| 1290 | You can forward ports on the SSH server machine in the other |
| 1291 | direction, too (so the connection will start at the server end and |
| 1292 | be sent down the secure connection to PuTTY, which will make the |
| 1293 | real connection to the destination). To work this way round, just |
| 1294 | click the \q{Remote} radio button instead of \q{Local}. |
| 1295 | |
| 1296 | \# FIXME: perhaps move this to a general port-forwarding section and |
| 1297 | \# just link to it here? |
| 1298 | |
| 1299 | \H{config-file} Storing configuration in a file |
| 1300 | |
| 1301 | PuTTY does not currently support storing its configuration in a file |
| 1302 | instead of the Registry. However, you can work around this with a |
| 1303 | couple of batch files. |
| 1304 | |
| 1305 | You will need a file called (say) \c{PUTTY.BAT} which imports the |
| 1306 | contents of a file into the Registry, then runs PuTTY, exports the |
| 1307 | contents of the Registry back into the file, and deletes the |
| 1308 | Registry entries. This can all be done using the Regedit command |
| 1309 | line options, so it's all automatic. Here is what you need in |
| 1310 | \c{PUTTY.BAT}: |
| 1311 | |
| 1312 | \c @ECHO OFF |
| 1313 | \c regedit /s putty.reg |
| 1314 | \c regedit /s puttyrnd.reg |
| 1315 | \c start /w putty.exe |
| 1316 | \c regedit /e puttynew.reg HKEY_CURRENT_USER\Software\SimonTatham\PuTTY |
| 1317 | \c copy puttynew.reg putty.reg |
| 1318 | \c del puttynew.reg |
| 1319 | \c regedit /s puttydel.reg |
| 1320 | |
| 1321 | This batch file needs two auxiliary files: \c{PUTTYRND.REG} which |
| 1322 | sets up an initial safe location for the \c{PUTTY.RND} random seed |
| 1323 | file, and \c{PUTTYDEL.REG} which destroys everything in the Registry |
| 1324 | once it's been successfully saved back to the file. |
| 1325 | |
| 1326 | Here is \c{PUTTYDEL.REG}: |
| 1327 | |
| 1328 | \c REGEDIT4 |
| 1329 | \c |
| 1330 | \c [-HKEY_CURRENT_USER\Software\SimonTatham\PuTTY] |
| 1331 | |
| 1332 | Here is an example \c{PUTTYRND.REG} file: |
| 1333 | |
| 1334 | \c REGEDIT4 |
| 1335 | \c |
| 1336 | \c [HKEY_CURRENT_USER\Software\SimonTatham\PuTTY] |
| 1337 | \c "RandSeedFile"="a:\putty.rnd" |
| 1338 | |
| 1339 | You should replace \c{a:\\putty.rnd} with the location where you |
| 1340 | want to store your random number data. If the aim is to carry around |
| 1341 | PuTTY and its settings on one floppy, you probably want to store it |
| 1342 | on the floppy. |