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1 | \input texinfo @c -*-texinfo-*- |
2 | @c %**start of header | |
6344cbf1 | 3 | @setfilename ../info/tramp |
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4 | @settitle TRAMP User Manual |
5 | @setchapternewpage odd | |
6 | @c %**end of header | |
7 | ||
8 | @c This is *so* much nicer :) | |
9 | @footnotestyle end | |
10 | ||
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11 | @c In the Tramp CVS, the version number is auto-frobbed from |
12 | @c configure.ac, so you should edit that file and run | |
13 | @c "autoconf && ./configure" to change the version number. | |
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14 | |
15 | @c Additionally, flags are set with respect to the Emacs flavor; and | |
16 | @c depending whether Tramp is packaged into (X)Emacs, or standalone. | |
17 | ||
b1a2b924 | 18 | @include trampver.texi |
fb7933a3 | 19 | |
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20 | @c Macro to make formatting of the tramp program name consistent. |
21 | @macro tramp | |
22 | @sc{tramp} | |
23 | @end macro | |
24 | ||
16674e4f | 25 | @c Macros for formatting a filename. |
884b79ec | 26 | @c trampfn is for a full filename, trampfnmhp means method, host, localname |
16674e4f | 27 | @c were given, and so on. |
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28 | @macro trampfn(method, user, host, localname) |
29 | @value{tramp-prefix}@value{method}@value{user}@@@value{host}@value{tramp-postfix}@value{localname} | |
16674e4f | 30 | @end macro |
fb7933a3 | 31 | |
f08d9f0e | 32 | @copying |
6b61353c | 33 | Copyright @copyright{} 1999, 2000, 2001, 2002, 2003, 2004 Free Software |
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34 | Foundation, Inc. |
35 | ||
6b61353c | 36 | @quotation |
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37 | Permission is granted to copy, distribute and/or modify this document |
38 | under the terms of the GNU Free Documentation License, Version 1.1 or | |
39 | any later version published by the Free Software Foundation; with no | |
40 | Invariant Sections, with the Front-Cover texts being ``A GNU | |
41 | Manual'', and with the Back-Cover Texts as in (a) below. A copy of the | |
42 | license is included in the section entitled ``GNU Free Documentation | |
43 | License'' in the Emacs manual. | |
44 | ||
45 | (a) The FSF's Back-Cover Text is: ``You have freedom to copy and modify | |
46 | this GNU Manual, like GNU software. Copies published by the Free | |
47 | Software Foundation raise funds for GNU development.'' | |
48 | ||
49 | This document is part of a collection distributed under the GNU Free | |
50 | Documentation License. If you want to distribute this document | |
51 | separately from the collection, you can do so by adding a copy of the | |
52 | license to the document, as described in section 6 of the license. | |
53 | @end quotation | |
54 | @end copying | |
55 | ||
41bed43c | 56 | @c Entries for @command{install-info} to use |
6b61353c | 57 | @dircategory @value{emacs-name} |
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58 | @direntry |
59 | * TRAMP: (tramp). Transparent Remote Access, Multiple Protocol | |
6b61353c | 60 | @value{emacs-name} remote file access via rsh and rcp. |
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61 | @end direntry |
62 | ||
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63 | @tex |
64 | ||
65 | @titlepage | |
16674e4f | 66 | @title @tramp{} version @trampver{} User Manual |
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67 | |
68 | @author by Daniel Pittman | |
69 | @author based on documentation by Kai Gro@ss{}johann | |
f08d9f0e | 70 | |
fb7933a3 | 71 | @page |
f08d9f0e | 72 | @insertcopying |
fb7933a3 | 73 | |
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74 | @end titlepage |
75 | @page | |
76 | ||
77 | @end tex | |
78 | ||
79 | @ifnottex | |
92eeeafc | 80 | @node Top, Overview, (dir), (dir) |
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81 | @top @tramp{} version @trampver{} User Manual |
82 | ||
83 | This file documents @tramp{} version @trampver{}, a remote file | |
84 | editing package for @value{emacs-name}. | |
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85 | |
86 | @tramp{} stands for `Transparent Remote (file) Access, Multiple | |
87 | Protocol'. This package provides remote file editing, similar to | |
16674e4f | 88 | @value{ftp-package-name}. |
fb7933a3 | 89 | |
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90 | The difference is that @value{ftp-package-name} uses FTP to transfer |
91 | files between the local and the remote host, whereas @tramp{} uses a | |
92 | combination of @command{rsh} and @command{rcp} or other work-alike | |
93 | programs, such as @command{ssh}/@command{scp}. | |
fb7933a3 | 94 | |
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95 | You can find the latest version of this document on the web at |
96 | @uref{http://www.freesoftware.fsf.org/tramp/}. | |
97 | ||
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98 | @c Pointer to the other Emacs flavor is necessary only in case of |
99 | @c standalone installation. Text taken from trampinst.texi. | |
100 | @ifset tramp-inst | |
101 | @otherflavor{} | |
102 | @end ifset | |
103 | ||
fb7933a3 | 104 | @ifhtml |
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105 | @ifset jamanual |
106 | This manual is also available as a @uref{@value{japanese-manual}, | |
107 | Japanese translation}. | |
108 | @end ifset | |
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109 | |
110 | The latest release of @tramp{} is available for | |
6b61353c | 111 | @uref{http://savannah.nongnu.org/download/tramp/, |
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112 | download}, or you may see @ref{Obtaining @tramp{}} for more details, |
113 | including the CVS server details. | |
114 | ||
6b61353c | 115 | @tramp{} also has a @uref{http://savannah.nongnu.org/projects/tramp/, |
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116 | Savannah Project Page}. |
117 | @end ifhtml | |
118 | ||
119 | There is a mailing list for @tramp{}, available at | |
120 | @email{tramp-devel@@mail.freesoftware.fsf.org}, and archived at | |
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121 | @uref{http://savannah.nongnu.org/mail/?group=tramp, Savannah Mail |
122 | Archive}. | |
123 | @ifhtml | |
124 | Older archives are located at | |
125 | @uref{http://sourceforge.net/mailarchive/forum.php?forum=tramp-devel, | |
126 | SourceForge Mail Archive} and | |
127 | @uref{http://www.mail-archive.com/emacs-rcp@@ls6.cs.uni-dortmund.de/, | |
128 | The Mail Archive}. | |
129 | @c in HTML output, there's no new paragraph. | |
130 | @*@* | |
131 | @end ifhtml | |
fb7933a3 | 132 | |
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133 | @insertcopying |
134 | ||
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135 | @end ifnottex |
136 | ||
137 | @menu | |
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138 | * Overview:: What @tramp{} can and cannot do. |
139 | ||
140 | For the end user: | |
7e190783 | 141 | |
18d6d595 | 142 | * Obtaining @tramp{}:: How to obtain @tramp{}. |
16674e4f | 143 | * History:: History of @tramp{}. |
7e190783 | 144 | @ifset tramp-inst |
16674e4f | 145 | * Installation:: Installing @tramp{} with your @value{emacs-name}. |
7e190783 | 146 | @end ifset |
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147 | * Configuration:: Configuring @tramp{} for use. |
148 | * Usage:: An overview of the operation of @tramp{}. | |
16674e4f | 149 | * Bug Reports:: Reporting Bugs and Problems. |
fb7933a3 | 150 | * Frequently Asked Questions:: Questions and answers from the mailing list. |
6b61353c | 151 | * Concept Index:: An item for each concept. |
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152 | |
153 | For the developer: | |
7e190783 | 154 | |
fb7933a3 | 155 | * Version Control:: The inner workings of remote version control. |
884b79ec | 156 | * Files directories and localnames:: How file names, directories and localnames are mangled and managed. |
16674e4f | 157 | * Issues:: Debatable Issues and What Was Decided. |
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158 | |
159 | @detailmenu | |
160 | --- The Detailed Node Listing --- | |
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161 | @c |
162 | @ifset tramp-inst | |
163 | Installing @tramp{} with your @value{emacs-name} | |
164 | ||
165 | * Installation parameters:: Parameters in order to control installation. | |
166 | * Load paths:: How to plug-in @tramp{} into your environment. | |
6b61353c | 167 | * Japanese manual:: Japanese manual. |
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168 | |
169 | @end ifset | |
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170 | |
171 | Configuring @tramp{} for use | |
172 | ||
173 | * Connection types:: Types of connections made to remote machines. | |
174 | * Inline methods:: Inline methods. | |
175 | * External transfer methods:: External transfer methods. | |
176 | * Multi-hop Methods:: Connecting to a remote host using multiple hops. | |
177 | * Default Method:: Selecting a default method. | |
178 | * Customizing Methods:: Using Non-Standard Methods. | |
16674e4f | 179 | * Customizing Completion:: Selecting config files for user/host name completion. |
6b61353c | 180 | * Password caching:: Reusing passwords for several connections. |
fb7933a3 | 181 | * Remote Programs:: How @tramp{} finds and uses programs on the remote machine. |
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182 | * Remote shell setup:: Remote shell setup hints. |
183 | * Windows setup hints:: Issues with Cygwin ssh. | |
b1a2b924 | 184 | * Auto-save and Backup:: Auto-save and Backup. |
fb7933a3 | 185 | |
6b61353c | 186 | Using @tramp{} |
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187 | |
188 | * Filename Syntax:: @tramp{} filename conventions. | |
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189 | * Multi-hop filename syntax:: Multi-hop filename conventions. |
190 | * Filename completion:: Filename completion. | |
191 | * Dired:: Dired. | |
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192 | |
193 | The inner workings of remote version control | |
194 | ||
195 | * Version Controlled Files:: Determining if a file is under version control. | |
196 | * Remote Commands:: Executing the version control commands on the remote machine. | |
197 | * Changed workfiles:: Detecting if the working file has changed. | |
198 | * Checking out files:: Bringing the workfile out of the repository. | |
16674e4f | 199 | * Miscellaneous Version Control:: Things related to Version Control that don't fit elsewhere. |
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200 | |
201 | Things related to Version Control that don't fit elsewhere | |
202 | ||
203 | * Remote File Ownership:: How VC determines who owns a workfile. | |
204 | * Back-end Versions:: How VC determines what release your RCS is. | |
205 | ||
7e190783 | 206 | How file names, directories and localnames are mangled and managed |
fb7933a3 | 207 | |
b1a2b924 | 208 | * Localname deconstruction:: Breaking a localname into its components. |
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209 | |
210 | @end detailmenu | |
211 | @end menu | |
212 | ||
fb7933a3 | 213 | @node Overview |
6b61353c | 214 | @chapter An overview of @tramp{} |
92eeeafc | 215 | @cindex overview |
fb7933a3 | 216 | |
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217 | After the installation of @tramp{} into your @value{emacs-name}, you |
218 | will be able to access files on remote machines as though they were | |
219 | local. Access to the remote file system for editing files, version | |
220 | control, and @command{dired} are transparently enabled. | |
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221 | |
222 | Your access to the remote machine can be with the @command{rsh}, | |
223 | @command{rlogin}, @command{telnet} programs or with any similar | |
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224 | connection method. This connection must pass @acronym{ASCII} |
225 | successfully to be usable but need not be 8-bit clean. | |
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226 | |
227 | The package provides support for @command{ssh} connections out of the | |
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228 | box, one of the more common uses of the package. This allows |
229 | relatively secure access to machines, especially if @command{ftp} | |
230 | access is disabled. | |
fb7933a3 | 231 | |
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232 | The majority of activity carried out by @tramp{} requires only that |
233 | the remote login is possible and is carried out at the terminal. In | |
234 | order to access remote files @tramp{} needs to transfer their content | |
235 | to the local machine temporarily. | |
fb7933a3 | 236 | |
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237 | @tramp{} can transfer files between the machines in a variety of ways. |
238 | The details are easy to select, depending on your needs and the | |
239 | machines in question. | |
fb7933a3 | 240 | |
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241 | The fastest transfer methods (for large files) rely on a remote file |
242 | transfer package such as @command{rcp}, @command{scp} or | |
243 | @command{rsync}. The use of these methods is only possible if the | |
244 | file copy command does not ask for a password for the remote machine. | |
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245 | |
246 | If the remote copy methods are not suitable for you, @tramp{} also | |
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247 | supports the use of encoded transfers directly through the shell. |
248 | This requires that the @command{mimencode} or @command{uuencode} tools | |
249 | are available on the remote machine. These methods are generally | |
250 | faster for small files. | |
fb7933a3 | 251 | |
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252 | Within these limitations, @tramp{} is quite powerful. It is worth |
253 | noting that, as of the time of writing, it is far from a polished | |
254 | end-user product. For a while yet you should expect to run into rough | |
255 | edges and problems with the code now and then. | |
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256 | |
257 | It is finished enough that the developers use it for day to day work but | |
258 | the installation and setup can be a little difficult to master, as can | |
259 | the terminology. | |
260 | ||
261 | @tramp{} is still under active development and any problems you encounter, | |
262 | trivial or major, should be reported to the @tramp{} developers. | |
263 | @xref{Bug Reports}. | |
264 | ||
265 | ||
266 | @subsubheading Behind the scenes | |
92eeeafc | 267 | @cindex behind the scenes |
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268 | @cindex details of operation |
269 | @cindex how it works | |
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270 | |
271 | This section tries to explain what goes on behind the scenes when you | |
272 | access a remote file through @tramp{}. | |
273 | ||
274 | Suppose you type @kbd{C-x C-f} and enter part of an @tramp{} file name, | |
275 | then hit @kbd{@key{TAB}} for completion. Suppose further that this is | |
276 | the first time that @tramp{} is invoked for the host in question. Here's | |
277 | what happens: | |
278 | ||
279 | @itemize | |
280 | @item | |
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281 | @tramp{} discovers that it needs a connection to the host. So it |
282 | invokes @samp{telnet @var{host}} or @samp{rsh @var{host} -l | |
283 | @var{user}} or a similar tool to connect to the remote host. | |
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284 | Communication with this process happens through an |
285 | @value{emacs-name} buffer, that is, the output from the remote end | |
286 | goes into a buffer. | |
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287 | |
288 | @item | |
289 | The remote host may prompt for a login name (for @command{telnet}). The | |
290 | login name is given in the file name, so @tramp{} sends the login name and | |
291 | a newline. | |
292 | ||
293 | @item | |
294 | The remote host may prompt for a password or pass phrase (for | |
295 | @command{rsh} or for @command{telnet} after sending the login name). | |
296 | @tramp{} displays the prompt in the minibuffer, asking you for the | |
297 | password or pass phrase. | |
298 | ||
299 | You enter the password or pass phrase. @tramp{} sends it to the remote | |
300 | host, followed by a newline. | |
301 | ||
302 | @item | |
303 | @tramp{} now waits for the shell prompt or for a message that the login | |
304 | failed. | |
305 | ||
306 | If @tramp{} sees neither of them after a certain period of time (a minute, | |
307 | say), then it issues an error message saying that it couldn't find the | |
308 | remote shell prompt and shows you what the remote host has sent. | |
309 | ||
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310 | If @tramp{} sees a @samp{login failed} message, it tells you so, |
311 | aborts the login attempt and allows you to try again. | |
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312 | |
313 | @item | |
314 | Suppose that the login was successful and @tramp{} sees the shell prompt | |
315 | from the remote host. Now @tramp{} invokes @command{/bin/sh} because | |
316 | Bourne shells and C shells have different command | |
317 | syntaxes.@footnote{Invoking @command{/bin/sh} will fail if your login | |
92eeeafc | 318 | shell doesn't recognize @samp{exec /bin/sh} as a valid command. |
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319 | Maybe you use the Scheme shell @command{scsh}@dots{}} |
320 | ||
321 | After the Bourne shell has come up, @tramp{} sends a few commands to | |
322 | ensure a good working environment. It turns off echoing, it sets the | |
323 | shell prompt, and a few other things. | |
324 | ||
325 | @item | |
326 | Now the remote shell is up and it good working order. Remember, what | |
327 | was supposed to happen is that @tramp{} tries to find out what files exist | |
328 | on the remote host so that it can do filename completion. | |
329 | ||
330 | So, @tramp{} basically issues @command{cd} and @command{ls} commands and | |
331 | also sometimes @command{echo} with globbing. Another command that is | |
332 | often used is @command{test} to find out whether a file is writable or a | |
333 | directory or the like. The output of each command is parsed for the | |
334 | necessary operation. | |
335 | ||
336 | @item | |
337 | Suppose you are finished with filename completion, have entered @kbd{C-x | |
338 | C-f}, a full file name and hit @kbd{@key{RET}}. Now comes the time to | |
339 | transfer the file contents from the remote host to the local host so | |
340 | that you can edit them. | |
341 | ||
342 | See above for an explanation of how @tramp{} transfers the file contents. | |
343 | ||
92eeeafc | 344 | For inline transfers, @tramp{} issues a command like @samp{mimencode -b |
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345 | /path/to/remote/file}, waits until the output has accumulated in the |
346 | buffer that's used for communication, then decodes that output to | |
347 | produce the file contents. | |
348 | ||
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349 | For out-of-band transfers, @tramp{} issues a command like the following: |
350 | @example | |
351 | rcp user@@host:/path/to/remote/file /tmp/tramp.4711 | |
352 | @end example | |
353 | It then reads the local temporary file @file{/tmp/tramp.4711} into a | |
354 | buffer and deletes the temporary file. | |
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355 | |
356 | @item | |
357 | You now edit the buffer contents, blithely unaware of what has happened | |
358 | behind the scenes. (Unless you have read this section, that is.) When | |
359 | you are finished, you type @kbd{C-x C-s} to save the buffer. | |
360 | ||
361 | @item | |
362 | Again, @tramp{} transfers the file contents to the remote host either | |
363 | inline or out-of-band. This is the reverse of what happens when reading | |
364 | the file. | |
365 | ||
366 | @end itemize | |
367 | ||
368 | I hope this has provided you with a basic overview of what happens | |
369 | behind the scenes when you open a file with @tramp{}. | |
370 | ||
371 | ||
372 | @c For the end user | |
373 | @node Obtaining @tramp{} | |
374 | @chapter Obtaining @tramp{}. | |
6b61353c | 375 | @cindex obtaining @tramp{} |
fb7933a3 | 376 | |
b1a2b924 KG |
377 | @tramp{} is freely available on the Internet and the latest release |
378 | may be downloaded from | |
379 | @uref{http://savannah.nongnu.org/download/tramp/}. This | |
380 | release includes the full documentation and code for @tramp{}, | |
381 | suitable for installation. But Emacs (21.4 or later) includes | |
382 | @tramp{} already, and there is a @tramp{} package for XEmacs, as well. | |
383 | So maybe it is easier to just use those. But if you want the bleeding | |
92eeeafc | 384 | edge, read on@dots{...} |
fb7933a3 | 385 | |
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386 | For the especially brave, @tramp{} is available from CVS. The CVS |
387 | version is the latest version of the code and may contain incomplete | |
388 | features or new issues. Use these versions at your own risk. | |
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389 | |
390 | Instructions for obtaining the latest development version of @tramp{} | |
16674e4f | 391 | from CVS can be found by going to the Savannah project page at the |
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392 | following URL and then clicking on the CVS link in the navigation bar |
393 | at the top. | |
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394 | |
395 | @noindent | |
6b61353c | 396 | @uref{http://savannah.nongnu.org/projects/tramp/} |
16674e4f KG |
397 | |
398 | @noindent | |
399 | Or follow the example session below: | |
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400 | |
401 | @example | |
16674e4f | 402 | ] @strong{cd ~/@value{emacs-dir}} |
6b61353c KH |
403 | ] @strong{export CVS_RSH="ssh"} |
404 | ] @strong{cvs -z3 -d:ext:anoncvs@@savannah.nongnu.org:/cvsroot/tramp co tramp} | |
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405 | @end example |
406 | ||
16674e4f | 407 | @noindent |
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408 | You should now have a directory @file{~/@value{emacs-dir}/tramp} |
409 | containing the latest version of @tramp{}. You can fetch the latest | |
410 | updates from the repository by issuing the command: | |
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411 | |
412 | @example | |
16674e4f | 413 | ] @strong{cd ~/@value{emacs-dir}/tramp} |
6b61353c | 414 | ] @strong{export CVS_RSH="ssh"} |
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415 | ] @strong{cvs update -d} |
416 | @end example | |
417 | ||
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418 | @noindent |
419 | Once you've got updated files from the CVS repository, you need to run | |
420 | @command{autoconf} in order to get an up-to-date @file{configure} | |
421 | script: | |
422 | ||
423 | @example | |
424 | ] @strong{cd ~/@value{emacs-dir}/tramp} | |
425 | ] @strong{autoconf} | |
426 | @end example | |
427 | ||
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428 | |
429 | @node History | |
430 | @chapter History of @tramp{} | |
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431 | @cindex history |
432 | @cindex development history | |
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433 | |
434 | Development was started end of November 1998. The package was called | |
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435 | @file{rssh.el}, back then. It only provided one method to access a |
436 | file, using @command{ssh} to log in to a remote host and using | |
437 | @command{scp} to transfer the file contents. After a while, the name | |
438 | was changed to @file{rcp.el}, and now it's @tramp{}. Along the way, | |
439 | many more methods for getting a remote shell and for transferring the | |
440 | file contents were added. Support for VC was added. | |
fb7933a3 | 441 | |
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442 | The most recent addition of major features were the multi-hop methods |
443 | added in April 2000 and the unification of @tramp{} and Ange-FTP | |
444 | filenames in July 2002. | |
fb7933a3 | 445 | |
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446 | @c Installation chapter is necessary only in case of standalone |
447 | @c installation. Text taken from trampinst.texi. | |
448 | @ifset tramp-inst | |
449 | @installationchapter{} | |
16674e4f | 450 | @end ifset |
fb7933a3 | 451 | |
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452 | @node Configuration |
453 | @chapter Configuring @tramp{} for use | |
92eeeafc | 454 | @cindex configuration |
fb7933a3 | 455 | |
92eeeafc | 456 | @cindex default configuration |
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457 | @tramp{} is (normally) fully functional when it is initially installed. |
458 | It is initially configured to use the @command{ssh} program to connect | |
459 | to the remote host and to use base64 or uu encoding to transfer the | |
460 | files through that shell connection. So in the easiest case, you just | |
461 | type @kbd{C-x C-f} and then enter the filename | |
462 | @file{@value{tramp-prefix}@var{user}@@@var{machine}@value{tramp-postfix}@var{/path/to.file}}. | |
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463 | |
464 | On some hosts, there are problems with opening a connection. These are | |
465 | related to the behavior of the remote shell. See @xref{Remote shell | |
466 | setup}, for details on this. | |
467 | ||
92eeeafc KG |
468 | If you do not wish to use these commands to connect to the remote |
469 | host, you should change the default connection and transfer method | |
6b61353c | 470 | that @tramp{} uses. There are several different methods that @tramp{} |
92eeeafc KG |
471 | can use to connect to remote machines and transfer files |
472 | (@pxref{Connection types}). | |
fb7933a3 | 473 | |
6b61353c KH |
474 | If you don't know which method is right for you, see @xref{Default |
475 | Method}. | |
476 | ||
fb7933a3 KG |
477 | |
478 | @menu | |
479 | * Connection types:: Types of connections made to remote machines. | |
480 | * Inline methods:: Inline methods. | |
481 | * External transfer methods:: External transfer methods. | |
482 | * Multi-hop Methods:: Connecting to a remote host using multiple hops. | |
483 | * Default Method:: Selecting a default method. | |
6b61353c KH |
484 | Here we also try to help those who |
485 | don't have the foggiest which method | |
486 | is right for them. | |
fb7933a3 | 487 | * Customizing Methods:: Using Non-Standard Methods. |
16674e4f | 488 | * Customizing Completion:: Selecting config files for user/host name completion. |
6b61353c | 489 | * Password caching:: Reusing passwords for several connections. |
fb7933a3 KG |
490 | * Remote Programs:: How @tramp{} finds and uses programs on the remote machine. |
491 | * Remote shell setup:: Remote shell setup hints. | |
492 | * Windows setup hints:: Issues with Cygwin ssh. | |
b1a2b924 | 493 | * Auto-save and Backup:: Auto-save and Backup. |
fb7933a3 KG |
494 | @end menu |
495 | ||
496 | ||
497 | @node Connection types | |
498 | @section Types of connections made to remote machines. | |
92eeeafc | 499 | @cindex connection types, overview |
fb7933a3 KG |
500 | |
501 | There are two basic types of transfer methods, each with its own | |
92eeeafc | 502 | advantages and limitations. Both types of connection make use of a |
fb7933a3 KG |
503 | remote shell access program such as @command{rsh}, @command{ssh} or |
504 | @command{telnet} to connect to the remote machine. | |
505 | ||
6b61353c | 506 | This connection is used to perform many of the operations that @tramp{} |
fb7933a3 KG |
507 | requires to make the remote file system transparently accessible from |
508 | the local machine. It is only when visiting files that the methods | |
509 | differ. | |
510 | ||
92eeeafc KG |
511 | @cindex inline methods |
512 | @cindex external transfer methods | |
513 | @cindex external methods | |
514 | @cindex out-of-band methods | |
515 | @cindex methods, inline | |
516 | @cindex methods, external transfer | |
517 | @cindex methods, out-of-band | |
518 | Loading or saving a remote file requires that the content of the file | |
16674e4f KG |
519 | be transfered between the two machines. The content of the file can be |
520 | transfered over the same connection used to log in to the remote | |
521 | machine or the file can be transfered through another connection using | |
92eeeafc KG |
522 | a remote copy program such as @command{rcp}, @command{scp} or |
523 | @command{rsync}. The former are called @dfn{inline methods}, the | |
524 | latter are called @dfn{out-of-band methods} or @dfn{external transfer | |
525 | methods} (@dfn{external methods} for short). | |
fb7933a3 KG |
526 | |
527 | The performance of the external transfer methods is generally better | |
92eeeafc KG |
528 | than that of the inline methods, at least for large files. This is |
529 | caused by the need to encode and decode the data when transferring | |
530 | inline. | |
fb7933a3 KG |
531 | |
532 | The one exception to this rule are the @command{scp} based transfer | |
533 | methods. While these methods do see better performance when actually | |
534 | transferring files, the overhead of the cryptographic negotiation at | |
535 | startup may drown out the improvement in file transfer times. | |
536 | ||
537 | External transfer methods do require that the remote copy command is not | |
538 | interactive --- that is, the command does not prompt you for a password. | |
539 | If you cannot perform remote copies without a password, you will need to | |
540 | use an inline transfer method to work with @tramp{}. | |
541 | ||
92eeeafc KG |
542 | @cindex multi-hop methods |
543 | @cindex methods, multi-hop | |
fb7933a3 KG |
544 | A variant of the inline methods are the @dfn{multi-hop methods}. |
545 | These methods allow you to connect a remote host using a number `hops', | |
546 | each of which connects to a different host. This is useful if you are | |
547 | in a secured network where you need to go through a bastion host to | |
548 | connect to the outside world. | |
549 | ||
550 | ||
551 | @node Inline methods | |
552 | @section Inline methods | |
92eeeafc KG |
553 | @cindex inline methods |
554 | @cindex methods, inline | |
fb7933a3 KG |
555 | |
556 | The inline methods in @tramp{} are quite powerful and can work in | |
557 | situations where you cannot use an external transfer program to connect. | |
558 | Inline methods are the only methods that work when connecting to the | |
559 | remote machine via telnet. (There are also strange inline methods which | |
560 | allow you to transfer files between @emph{user identities} rather than | |
561 | hosts, see below.) | |
562 | ||
563 | These methods depend on the existence of a suitable encoding and | |
6b61353c KH |
564 | decoding command on remote machine. Locally, @tramp{} may be able to |
565 | use features of @value{emacs-name} to decode and encode the files or | |
566 | it may require access to external commands to perform that task. | |
fb7933a3 | 567 | |
92eeeafc | 568 | @cindex uuencode |
92eeeafc KG |
569 | @cindex mimencode |
570 | @cindex base-64 encoding | |
f08d9f0e KG |
571 | @tramp{} checks the availability and usability of commands like |
572 | @command{mimencode} (part of the @command{metamail} package) or | |
573 | @command{uuencode} on the remote host. The first reliable command | |
574 | will be used. The search path can be customized, see @ref{Remote | |
575 | Programs}. | |
fb7933a3 | 576 | |
abc6be8d | 577 | If both commands aren't available on the remote host, @tramp{} |
f08d9f0e KG |
578 | transfers a small piece of Perl code to the remote host, and tries to |
579 | apply it for encoding and decoding. | |
fb7933a3 | 580 | |
fb7933a3 | 581 | |
f08d9f0e KG |
582 | @table @asis |
583 | @item @option{rsh} | |
584 | @cindex method rsh | |
585 | @cindex rsh method | |
fb7933a3 | 586 | |
f08d9f0e KG |
587 | Connect to the remote host with @command{rsh}. Due to the unsecure |
588 | connection it is recommended for very local host topology only. | |
fb7933a3 | 589 | |
41bed43c KG |
590 | On operating systems which provide the command @command{remsh} instead |
591 | of @command{rsh}, you can use the method @option{remsh}. This is true | |
592 | for HP-UX or Cray UNICOS, for example. | |
593 | ||
fb7933a3 | 594 | |
f08d9f0e KG |
595 | @item @option{ssh} |
596 | @cindex method ssh | |
597 | @cindex ssh method | |
fb7933a3 | 598 | |
f08d9f0e KG |
599 | Connect to the remote host with @command{ssh}. This is identical to |
600 | the previous option except that the @command{ssh} package is used, | |
601 | making the connection more secure. | |
fb7933a3 | 602 | |
f08d9f0e KG |
603 | There are also two variants, @option{ssh1} and @option{ssh2}, that |
604 | call @samp{ssh -1} and @samp{ssh -2}, respectively. This way, you can | |
90dc758d KG |
605 | explicitly select whether you want to use the SSH protocol version 1 |
606 | or 2 to connect to the remote host. (You can also specify in | |
607 | @file{~/.ssh/config}, the SSH configuration file, which protocol | |
f08d9f0e | 608 | should be used, and use the regular @option{ssh} method.) |
90dc758d | 609 | |
f08d9f0e KG |
610 | Two other variants, @option{ssh1_old} and @option{ssh2_old}, use the |
611 | @command{ssh1} and @command{ssh2} commands explicitly. If you don't | |
612 | know what these are, you do not need these options. | |
fb7933a3 | 613 | |
16674e4f | 614 | All the methods based on @command{ssh} have an additional kludgy |
8e3a1104 KG |
615 | feature: you can specify a host name which looks like @file{host#42} |
616 | (the real host name, then a hash sign, then a port number). This | |
617 | means to connect to the given host but to also pass @code{-p 42} as | |
618 | arguments to the @command{ssh} command. | |
619 | ||
fb7933a3 | 620 | |
f08d9f0e KG |
621 | @item @option{telnet} |
622 | @cindex method telnet | |
623 | @cindex telnet method | |
fb7933a3 | 624 | |
f08d9f0e KG |
625 | Connect to the remote host with @command{telnet}. This is as unsecure |
626 | as the @option{rsh} method. | |
fb7933a3 | 627 | |
fb7933a3 | 628 | |
f08d9f0e | 629 | @item @option{su} |
92eeeafc KG |
630 | @cindex method su |
631 | @cindex su method | |
fb7933a3 | 632 | |
f08d9f0e KG |
633 | This method does not connect to a remote host at all, rather it uses |
634 | the @command{su} program to allow you to edit files as another user. | |
fb7933a3 | 635 | |
fb7933a3 | 636 | |
f08d9f0e KG |
637 | @item @option{sudo} |
638 | @cindex method sudo | |
639 | @cindex sudo method | |
fb7933a3 | 640 | |
f08d9f0e | 641 | This is similar to the @option{su} method, but it uses @command{sudo} |
fb7933a3 KG |
642 | rather than @command{su} to become a different user. |
643 | ||
644 | Note that @command{sudo} must be configured to allow you to start a | |
645 | shell as the user. It would be nice if it was sufficient if | |
f08d9f0e KG |
646 | @command{ls} and @command{mimencode} were allowed, but that is not |
647 | easy to implement, so I haven't got around to it, yet. | |
fb7933a3 | 648 | |
fb7933a3 | 649 | |
f08d9f0e KG |
650 | @item @option{sshx} |
651 | @cindex method sshx | |
652 | @cindex sshx method | |
653 | @cindex Cygwin (with sshx method) | |
fb7933a3 | 654 | |
6b61353c | 655 | As you would expect, this is similar to @option{ssh}, only a little |
f08d9f0e | 656 | different. Whereas @option{ssh} opens a normal interactive shell on |
92eeeafc | 657 | the remote host, this option uses @samp{ssh -t -t @var{host} -l |
16674e4f | 658 | @var{user} /bin/sh} to open a connection. This is useful for users |
92eeeafc KG |
659 | where the normal login shell is set up to ask them a number of |
660 | questions when logging in. This procedure avoids these questions, and | |
661 | just gives @tramp{} a more-or-less `standard' login shell to work | |
662 | with. | |
fb7933a3 | 663 | |
83fa16cf KG |
664 | Note that this procedure does not eliminate questions asked by |
665 | @command{ssh} itself. For example, @command{ssh} might ask ``Are you | |
666 | sure you want to continue connecting?'' if the host key of the remote | |
abc6be8d | 667 | host is not known. @tramp{} does not know how to deal with such a |
83fa16cf KG |
668 | question (yet), therefore you will need to make sure that you can log |
669 | in without such questions. | |
670 | ||
fb7933a3 | 671 | This is also useful for Windows users where @command{ssh}, when |
6b61353c KH |
672 | invoked from an @value{emacs-name} buffer, tells them that it is not |
673 | allocating a pseudo tty. When this happens, the login shell is wont | |
674 | to not print any shell prompt, which confuses @tramp{} mightily. For | |
675 | reasons unknown, some Windows ports for @command{ssh} (maybe the | |
676 | Cygwin one) require the doubled @samp{-t} option. | |
fb7933a3 | 677 | |
92eeeafc | 678 | This supports the @samp{-p} kludge. |
8e3a1104 | 679 | |
fb7933a3 | 680 | |
f08d9f0e KG |
681 | @item @option{krlogin} |
682 | @cindex method krlogin | |
683 | @cindex km krlogin | |
684 | @cindex Kerberos (with krlogin method) | |
fb7933a3 | 685 | |
f08d9f0e | 686 | This method is also similar to @option{ssh}. It only uses the |
fb7933a3 KG |
687 | @command{krlogin -x} command to log in to the remote host. |
688 | ||
689 | ||
f08d9f0e KG |
690 | @item @option{plink} |
691 | @cindex method plink | |
692 | @cindex plink method | |
fb7933a3 KG |
693 | |
694 | This method is mostly interesting for Windows users using the PuTTY | |
92eeeafc | 695 | implementation of SSH. It uses @samp{plink -ssh} to log in to the |
fb7933a3 KG |
696 | remote host. |
697 | ||
41bed43c KG |
698 | Additionally, the method @option{plink1} is provided, which calls |
699 | @samp{plink -1 -ssh} in order to use SSH protocol version 1 | |
700 | explicitely. | |
701 | ||
fb7933a3 KG |
702 | CCC: Do we have to connect to the remote host once from the command |
703 | line to accept the SSH key? Maybe this can be made automatic? | |
704 | ||
abc6be8d KG |
705 | CCC: Does @command{plink} support the @samp{-p} option? @tramp{} will |
706 | support that, anyway. | |
8e3a1104 | 707 | |
92eeeafc | 708 | @end table |
fb7933a3 KG |
709 | |
710 | ||
711 | ||
712 | @node External transfer methods | |
713 | @section External transfer methods | |
92eeeafc KG |
714 | @cindex methods, external transfer |
715 | @cindex methods, out-of-band | |
716 | @cindex external transfer methods | |
717 | @cindex out-of-band methods | |
fb7933a3 KG |
718 | |
719 | The external transfer methods operate through multiple channels, using | |
720 | the remote shell connection for many actions while delegating file | |
721 | transfers to an external transfer utility. | |
722 | ||
723 | This saves the overhead of encoding and decoding that multiplexing the | |
724 | transfer through the one connection has with the inline methods. | |
725 | ||
726 | If you want to use an external transfer method you @emph{must} be able | |
727 | to execute the transfer utility to copy files to and from the remote | |
728 | machine without any interaction. | |
729 | ||
92eeeafc | 730 | @cindex ssh-agent |
fb7933a3 KG |
731 | This means that you will need to use @command{ssh-agent} if you use the |
732 | @command{scp} program for transfers, or maybe your version of | |
733 | @command{scp} accepts a password on the command line.@footnote{PuTTY's | |
734 | @command{pscp} allows you to specify the password on the command line.} | |
735 | If you use @command{rsync} via @command{ssh} then the same rule must | |
736 | apply to that connection. | |
737 | ||
738 | If you cannot get @command{scp} to run without asking for a password but | |
739 | would still like to use @command{ssh} to secure your connection, have a | |
740 | look at the @command{ssh} based inline methods. | |
741 | ||
742 | ||
92eeeafc | 743 | @table @asis |
fb7933a3 | 744 | @item @option{rcp} --- @command{rsh} and @command{rcp} |
92eeeafc KG |
745 | @cindex method rcp |
746 | @cindex rcp method | |
e28e4d20 KG |
747 | @cindex rcp (with rcp method) |
748 | @cindex rsh (with rcp method) | |
fb7933a3 KG |
749 | |
750 | This method uses the @command{rsh} and @command{rcp} commands to connect | |
41bed43c | 751 | to the remote machine and transfer files. This is probably the fastest |
fb7933a3 KG |
752 | connection method available. |
753 | ||
41bed43c KG |
754 | The alternative method @option{remcp} uses the @command{remsh} and |
755 | @command{rcp} commands. It should be applied on machines where | |
756 | @command{remsh} is used instead of @command{rsh}. | |
757 | ||
fb7933a3 KG |
758 | |
759 | @item @option{scp} --- @command{ssh} and @command{scp} | |
92eeeafc KG |
760 | @cindex method scp |
761 | @cindex scp method | |
e28e4d20 KG |
762 | @cindex scp (with scp method) |
763 | @cindex ssh (with scp method) | |
fb7933a3 KG |
764 | |
765 | Using @command{ssh} to connect to the remote host and @command{scp} to | |
766 | transfer files between the machines is the best method for securely | |
767 | connecting to a remote machine and accessing files. | |
768 | ||
769 | The performance of this option is also quite good. It may be slower than | |
770 | the inline methods when you often open and close small files however. | |
771 | The cost of the cryptographic handshake at the start of an @command{scp} | |
772 | session can begin to absorb the advantage that the lack of encoding and | |
773 | decoding presents. | |
774 | ||
f08d9f0e KG |
775 | There are also two variants, @option{scp1} and @option{scp2}, that |
776 | call @samp{ssh -1} and @samp{ssh -2}, respectively. This way, you can | |
777 | explicitly select whether you want to use the SSH protocol version 1 | |
778 | or 2 to connect to the remote host. (You can also specify in | |
779 | @file{~/.ssh/config}, the SSH configuration file, which protocol | |
6b61353c | 780 | should be used, and use the regular @option{scp} method.) |
f08d9f0e KG |
781 | |
782 | Two other variants, @option{scp1_old} and @option{scp2_old}, use the | |
783 | @command{ssh1} and @command{ssh2} commands explicitly. If you don't | |
784 | know what these are, you do not need these options. | |
785 | ||
16674e4f | 786 | All the @command{ssh} based methods support the kludgy @samp{-p} |
8e3a1104 | 787 | feature where you can specify a port number to connect to in the host |
abc6be8d | 788 | name. For example, the host name @file{host#42} tells @tramp{} to |
92eeeafc | 789 | specify @samp{-p 42} in the argument list for @command{ssh}. |
8e3a1104 | 790 | |
fb7933a3 KG |
791 | |
792 | @item @option{rsync} --- @command{ssh} and @command{rsync} | |
92eeeafc KG |
793 | @cindex method rsync |
794 | @cindex rsync method | |
e28e4d20 KG |
795 | @cindex rsync (with rsync method) |
796 | @cindex ssh (with rsync method) | |
fb7933a3 KG |
797 | |
798 | Using the @command{ssh} command to connect securely to the remote | |
799 | machine and the @command{rsync} command to transfer files is almost | |
800 | identical to the @option{scp} method. | |
801 | ||
802 | While @command{rsync} performs much better than @command{scp} when | |
803 | transferring files that exist on both hosts, this advantage is lost if | |
804 | the file exists only on one side of the connection. | |
805 | ||
806 | The @command{rsync} based method may be considerably faster than the | |
807 | @command{rcp} based methods when writing to the remote system. Reading | |
abc6be8d | 808 | files to the local machine is no faster than with a direct copy. |
fb7933a3 | 809 | |
92eeeafc | 810 | This method supports the @samp{-p} hack. |
8e3a1104 | 811 | |
fb7933a3 KG |
812 | |
813 | @item @option{scpx} --- @command{ssh} and @command{scp} | |
92eeeafc KG |
814 | @cindex method scpx |
815 | @cindex scpx method | |
e28e4d20 KG |
816 | @cindex scp (with scpx method) |
817 | @cindex ssh (with scpx method) | |
818 | @cindex Cygwin (with scpx method) | |
fb7933a3 | 819 | |
6b61353c | 820 | As you would expect, this is similar to @option{scp}, only a little |
92eeeafc KG |
821 | different. Whereas @option{scp} opens a normal interactive shell on |
822 | the remote host, this option uses @samp{ssh -t -t @var{host} -l | |
823 | @var{user} /bin/sh} to open a connection. This is useful for users | |
824 | where the normal login shell is set up to ask them a number of | |
825 | questions when logging in. This procedure avoids these questions, and | |
826 | just gives @tramp{} a more-or-less `standard' login shell to work | |
827 | with. | |
fb7933a3 KG |
828 | |
829 | This is also useful for Windows users where @command{ssh}, when | |
6b61353c KH |
830 | invoked from an @value{emacs-name} buffer, tells them that it is not |
831 | allocating a pseudo tty. When this happens, the login shell is wont | |
832 | to not print any shell prompt, which confuses @tramp{} mightily. | |
833 | Maybe this applies to the Cygwin port of SSH. | |
fb7933a3 | 834 | |
92eeeafc | 835 | This method supports the @samp{-p} hack. |
8e3a1104 | 836 | |
fb7933a3 KG |
837 | |
838 | @item @option{pscp} --- @command{plink} and @command{pscp} | |
92eeeafc KG |
839 | @cindex method pscp |
840 | @cindex pscp method | |
e28e4d20 KG |
841 | @cindex pscp (with pscp method) |
842 | @cindex plink (with pscp method) | |
843 | @cindex PuTTY (with pscp method) | |
fb7933a3 KG |
844 | |
845 | This method is similar to @option{scp}, but it uses the | |
846 | @command{plink} command to connect to the remote host, and it uses | |
847 | @command{pscp} for transferring the files. These programs are part | |
848 | of PuTTY, an SSH implementation for Windows. | |
849 | ||
92eeeafc | 850 | CCC: Does @command{plink} support the @samp{-p} hack? |
8e3a1104 | 851 | |
fb7933a3 KG |
852 | |
853 | @item @option{fcp} --- @command{fsh} and @command{fcp} | |
92eeeafc KG |
854 | @cindex method fcp |
855 | @cindex fcp method | |
e28e4d20 KG |
856 | @cindex fsh (with fcp method) |
857 | @cindex fcp (with fcp method) | |
fb7933a3 KG |
858 | |
859 | This method is similar to @option{scp}, but it uses the @command{fsh} | |
860 | command to connect to the remote host, and it uses @command{fcp} for | |
861 | transferring the files. @command{fsh/fcp} are a front-end for | |
862 | @command{ssh} which allow for reusing the same @command{ssh} session | |
863 | for submitting several commands. This avoids the startup overhead of | |
864 | @command{scp} (which has to establish a secure connection whenever it | |
865 | is called). Note, however, that you can also use one of the inline | |
866 | methods to achieve a similar effect. | |
867 | ||
92eeeafc KG |
868 | This method uses the command @samp{fsh @var{host} -l @var{user} |
869 | /bin/sh -i} to establish the connection, it does not work to just say | |
870 | @command{fsh @var{host} -l @var{user}}. | |
fb7933a3 | 871 | |
e28e4d20 KG |
872 | @cindex method fsh |
873 | @cindex fsh method | |
6b61353c | 874 | |
92eeeafc KG |
875 | There is no inline method using @command{fsh} as the multiplexing |
876 | provided by the program is not very useful in our context. @tramp{} | |
877 | opens just one connection to the remote host and then keeps it open, | |
878 | anyway. | |
879 | ||
f08d9f0e | 880 | |
f08d9f0e KG |
881 | @item @option{ftp} |
882 | @cindex method ftp | |
883 | @cindex ftp method | |
884 | ||
abc6be8d | 885 | This is not a native @tramp{} method. Instead of, it forwards all |
f08d9f0e | 886 | requests to @value{ftp-package-name}. |
6b61353c KH |
887 | @ifset xemacs |
888 | This works only for unified filenames, see @ref{Issues}. | |
f08d9f0e KG |
889 | @end ifset |
890 | ||
abc6be8d KG |
891 | |
892 | @item @option{smb} --- @command{smbclient} | |
893 | @cindex method smb | |
894 | @cindex smb method | |
895 | ||
896 | This is another not natural @tramp{} method. It uses the | |
897 | @command{smbclient} command on different Unices in order to connect to | |
898 | an SMB server. An SMB server might be a Samba (or CIFS) server on | |
899 | another UNIX host or, more interesting, a host running MS Windows. So | |
900 | far, it is tested towards MS Windows NT, MS Windows 2000, and MS | |
901 | Windows XP. | |
902 | ||
884b79ec | 903 | The first directory in the localname must be a share name on the remote |
abc6be8d KG |
904 | host. Remember, that the @code{$} character in which default shares |
905 | usually end, must be written @code{$$} due to environment variable | |
906 | substitution in file names. If no share name is given (i.e. remote | |
907 | directory @code{/}), all available shares are listed. | |
908 | ||
909 | Since authorization is done on share level, you will be prompted | |
910 | always for a password if you access another share on the same host. | |
6b61353c | 911 | This can be suppressed by @ref{Password caching}. |
abc6be8d KG |
912 | |
913 | MS Windows uses for authorization both a user name and a domain name. | |
914 | Because of this, the @tramp{} syntax has been extended: you can | |
915 | specify a user name which looks like @code{user%domain} (the real user | |
916 | name, then a percent sign, then the domain name). So, to connect to | |
917 | the machine @code{melancholia} as user @code{daniel} of the domain | |
918 | @code{BIZARRE}, and edit @file{.emacs} in the home directory (share | |
919 | @code{daniel$}) I would specify the filename | |
920 | @file{@value{tramp-prefix}smb@value{tramp-postfix-single-hop}daniel%BIZARRE@@melancholia@value{tramp-postfix}/daniel$$/.emacs}. | |
921 | ||
922 | The domain name as well as the user name are optional. If no user | |
923 | name is specified at all, the anonymous user (without password | |
924 | prompting) is assumed. This is different from all other @tramp{} | |
925 | methods, where in such a case the local user name is taken. | |
926 | ||
927 | The @option{smb} method supports the @samp{-p} hack. | |
928 | ||
6b61353c KH |
929 | @strong{Please note:} If @value{emacs-name} runs locally under MS |
930 | Windows, this method isn't available. Instead of, you can use UNC | |
931 | file names like @file{//melancholia/daniel$$/.emacs}. The only | |
932 | disadvantage is that there's no possibility to specify another user | |
933 | name. | |
abc6be8d | 934 | |
92eeeafc | 935 | @end table |
fb7933a3 KG |
936 | |
937 | @node Multi-hop Methods | |
938 | @section Connecting to a remote host using multiple hops | |
92eeeafc KG |
939 | @cindex multi-hop methods |
940 | @cindex methods, multi-hop | |
fb7933a3 KG |
941 | |
942 | Sometimes, the methods described before are not sufficient. Sometimes, | |
943 | it is not possible to connect to a remote host using a simple command. | |
944 | For example, if you are in a secured network, you might have to log in | |
945 | to a `bastion host' first before you can connect to the outside world. | |
946 | Of course, the target host may also require a bastion host. The format | |
947 | of multi-hop filenames is slightly different than the format of normal | |
948 | @tramp{} methods. | |
949 | ||
92eeeafc KG |
950 | @cindex method multi |
951 | @cindex multi method | |
884b79ec KG |
952 | A multi-hop file name specifies a method, a number of hops, and a |
953 | localname (path name on the remote system). The method name is always | |
f08d9f0e | 954 | @option{multi}. |
fb7933a3 | 955 | |
f08d9f0e KG |
956 | Each hop consists of a @dfn{hop method} specification, a user name and |
957 | a host name. The hop method can be an inline method only. The | |
958 | following hop methods are (currently) available: | |
fb7933a3 | 959 | |
92eeeafc KG |
960 | @table @option |
961 | @item telnet | |
962 | @cindex hop method telnet | |
963 | @cindex telnet hop method | |
fb7933a3 KG |
964 | |
965 | Uses the well-known @command{telnet} program to connect to the host. | |
966 | Whereas user name and host name are supplied in the file name, the | |
967 | user is queried for the password. | |
968 | ||
92eeeafc KG |
969 | @item rsh |
970 | @cindex hop method rsh | |
971 | @cindex rsh hop method | |
fb7933a3 KG |
972 | |
973 | This uses @command{rsh} to connect to the host. You do not need to | |
974 | enter a password unless @command{rsh} explicitly asks for it. | |
975 | ||
41bed43c KG |
976 | The variant @option{remsh} uses the @command{remsh} command. It |
977 | should be applied on machines where @command{remsh} is used instead of | |
978 | @command{rsh}. | |
979 | ||
92eeeafc KG |
980 | @item ssh |
981 | @cindex hop method ssh | |
982 | @cindex ssh hop method | |
fb7933a3 KG |
983 | |
984 | This uses @command{ssh} to connect to the host. You might have to enter | |
985 | a password or a pass phrase. | |
986 | ||
92eeeafc KG |
987 | @item su |
988 | @cindex hop method su | |
989 | @cindex su hop method | |
fb7933a3 KG |
990 | |
991 | This method does not actually contact a different host, but it allows | |
992 | you to become a different user on the host you're currently on. This | |
993 | might be useful if you want to edit files as root, but the remote host | |
994 | does not allow remote root logins. In this case you can use | |
995 | @option{telnet}, @option{rsh} or @option{ssh} to connect to the | |
996 | remote host as a non-root user, then use an @option{su} hop to become | |
997 | root. But @option{su} need not be the last hop in a sequence, you could | |
998 | also use it somewhere in the middle, if the need arises. | |
999 | ||
f08d9f0e | 1000 | Even though you @emph{must} specify both user and host with an |
fb7933a3 KG |
1001 | @option{su} hop, the host name is ignored and only the user name is |
1002 | used. | |
1003 | ||
92eeeafc KG |
1004 | @item sudo |
1005 | @cindex hop method sudo | |
1006 | @cindex sudo hop method | |
fb7933a3 KG |
1007 | |
1008 | This is similar to the @option{su} hop, except that it uses | |
1009 | @command{sudo} rather than @command{su} to become a different user. | |
1010 | ||
92eeeafc | 1011 | @end table |
fb7933a3 | 1012 | |
92eeeafc KG |
1013 | Some people might wish to use port forwarding with @command{ssh} or |
1014 | maybe they have to use a nonstandard port. This can be accomplished | |
1015 | by putting a stanza in @file{~/.ssh/config} for the account which | |
1016 | specifies a different port number for a certain host name. But it can | |
f08d9f0e KG |
1017 | also be accomplished within @tramp{}, by adding a multi-hop method. |
1018 | For example: | |
fb7933a3 KG |
1019 | |
1020 | @lisp | |
16674e4f KG |
1021 | (add-to-list |
1022 | 'tramp-multi-connection-function-alist | |
1023 | '("sshf" tramp-multi-connect-rlogin "ssh %h -l %u -p 4400%n")) | |
fb7933a3 KG |
1024 | @end lisp |
1025 | ||
16674e4f | 1026 | Now you can use an @code{sshf} hop which connects to port 4400 instead of |
fb7933a3 KG |
1027 | the standard port. |
1028 | ||
1029 | ||
1030 | @node Default Method | |
1031 | @section Selecting a default method | |
92eeeafc | 1032 | @cindex default method |
fb7933a3 | 1033 | |
92eeeafc | 1034 | @vindex tramp-default-method |
fb7933a3 | 1035 | When you select an appropriate transfer method for your typical usage |
6b61353c | 1036 | you should set the variable @code{tramp-default-method} to reflect that |
92eeeafc | 1037 | choice. This variable controls which method will be used when a method |
884b79ec | 1038 | is not specified in the @tramp{} file name. For example: |
fb7933a3 KG |
1039 | |
1040 | @lisp | |
1041 | (setq tramp-default-method "scp") | |
1042 | @end lisp | |
1043 | ||
92eeeafc KG |
1044 | @vindex tramp-default-method-alist |
1045 | You can also specify different methods for certain user/host | |
6b61353c | 1046 | combinations, via the variable @code{tramp-default-method-alist}. For |
f08d9f0e | 1047 | example, the following two lines specify to use the @option{ssh} |
92eeeafc KG |
1048 | method for all user names matching @samp{john} and the @option{rsync} |
1049 | method for all host names matching @samp{lily}. The third line | |
f08d9f0e | 1050 | specifies to use the @option{su} method for the user @samp{root} on |
92eeeafc KG |
1051 | the machine @samp{localhost}. |
1052 | ||
1053 | @lisp | |
f08d9f0e | 1054 | (add-to-list 'tramp-default-method-alist '("" "john" "ssh")) |
92eeeafc KG |
1055 | (add-to-list 'tramp-default-method-alist '("lily" "" "rsync")) |
1056 | (add-to-list 'tramp-default-method-alist | |
f08d9f0e | 1057 | '("\\`localhost\\'" "\\`root\\'" "su")) |
92eeeafc KG |
1058 | @end lisp |
1059 | ||
1060 | @noindent | |
1061 | See the documentation for the variable | |
6b61353c | 1062 | @code{tramp-default-method-alist} for more details. |
92eeeafc | 1063 | |
fb7933a3 KG |
1064 | External transfer methods are normally preferable to inline transfer |
1065 | methods, giving better performance. They may not be useful if you use | |
1066 | many remote machines where you cannot log in without a password. | |
1067 | ||
1068 | @xref{Inline methods}. | |
1069 | @xref{External transfer methods}. | |
1070 | @xref{Multi-hop Methods}. | |
1071 | ||
1072 | Another consideration with the selection of transfer methods is the | |
1073 | environment you will use them in and, especially when used over the | |
1074 | Internet, the security implications of your preferred method. | |
1075 | ||
1076 | The @command{rsh} and @command{telnet} methods send your password as | |
1077 | plain text as you log in to the remote machine, as well as transferring | |
1078 | the files in such a way that the content can easily be read from other | |
1079 | machines. | |
1080 | ||
1081 | If you need to connect to remote systems that are accessible from the | |
1082 | Internet, you should give serious thought to using @command{ssh} based | |
1083 | methods to connect. These provide a much higher level of security, | |
1084 | making it a non-trivial exercise for someone to obtain your password or | |
1085 | read the content of the files you are editing. | |
1086 | ||
6b61353c KH |
1087 | |
1088 | @subsection Which method is the right one for me? | |
1089 | @cindex choosing the right method | |
1090 | ||
1091 | Given all of the above, you are probably thinking that this is all fine | |
1092 | and good, but it's not helping you to choose a method! Right you are. | |
1093 | As a developer, we don't want to boss our users around but give them | |
1094 | maximum freedom instead. However, the reality is that some users would | |
1095 | like to have some guidance, so here I'll try to give you this guidance | |
1096 | without bossing you around. You tell me whether it works @dots{} | |
1097 | ||
1098 | My suggestion is to use an inline method. For large files, out-of-band | |
1099 | methods might be more efficient, but I guess that most people will want | |
1100 | to edit mostly small files. | |
1101 | ||
1102 | I guess that these days, most people can access a remote machine by | |
1103 | using @code{ssh}. So I suggest that you use the @code{ssh} method. | |
1104 | So, type @kbd{C-x C-f /ssh:root@@otherhost:/etc/motd @key{RET}} to | |
1105 | edit the @file{/etc/motd} file on the other host. | |
1106 | ||
1107 | If you can't use @code{ssh} to log in to the remote host, then select a | |
1108 | method that uses a program that works. For instance, Windows users | |
1109 | might like the @code{plink} method which uses the PuTTY implementation | |
1110 | of @code{ssh}. Or you use Kerberos and thus like @code{krlogin}. | |
1111 | ||
1112 | For the special case of editing files on the local host as another | |
1113 | user, see the @code{su} or @code{sudo} method. | |
1114 | ||
1115 | People who edit large files may want to consider @code{scp} instead of | |
1116 | @code{ssh}, or @code{pscp} instead of @code{plink}. These out-of-band | |
1117 | methods are faster than inline methods for large files. Note, however, | |
1118 | that out-of-band methods suffer from some limitations. Please try | |
1119 | first whether you really get a noticeable speed advantage from using an | |
1120 | out-of-band method! Maybe even for large files, inline methods are | |
1121 | fast enough. | |
1122 | ||
1123 | The reason why I'm suggesting to use inline methods is that they work | |
1124 | even if the remote end is asking you for a password. Out-of-band | |
1125 | methods don't work in this situation. Also, multi-hop methods are | |
1126 | inherently inline. | |
1127 | ||
1128 | ||
fb7933a3 KG |
1129 | @node Customizing Methods |
1130 | @section Using Non-Standard Methods | |
92eeeafc KG |
1131 | @cindex customizing methods |
1132 | @cindex using non-standard methods | |
1133 | @cindex create your own methods | |
fb7933a3 KG |
1134 | |
1135 | There is a variable @code{tramp-methods} which you can change if the | |
1136 | predefined methods don't seem right. | |
1137 | ||
1138 | For the time being, I'll refer you to the Lisp documentation of that | |
1139 | variable, accessible with @kbd{C-h v tramp-methods @key{RET}}. | |
1140 | ||
1141 | ||
16674e4f KG |
1142 | @node Customizing Completion |
1143 | @section Selecting config files for user/host name completion | |
1144 | @cindex customizing completion | |
1145 | @cindex selecting config files | |
1146 | @vindex tramp-completion-function-alist | |
1147 | ||
1148 | The variable @code{tramp-completion-function-alist} is intended to | |
abc6be8d | 1149 | customize which files are taken into account for user and host name |
16674e4f KG |
1150 | completion (@pxref{Filename completion}). For every method, it keeps |
1151 | a set of configuration files, accompanied by a Lisp function able to | |
1152 | parse that file. Entries in @code{tramp-completion-function-alist} | |
1153 | have the form (@var{method} @var{pair1} @var{pair2} ...). | |
1154 | ||
1155 | Each @var{pair} is composed of (@var{function} @var{file}). | |
1156 | @var{function} is responsible to extract user names and host names | |
1157 | from @var{file} for completion. There are two functions which access | |
1158 | this variable: | |
1159 | ||
1160 | @defun tramp-get-completion-function method | |
1161 | This function returns the list of completion functions for @var{method}. | |
1162 | ||
1163 | Example: | |
1164 | @example | |
1165 | (tramp-get-completion-function "rsh") | |
1166 | ||
1167 | @result{} ((tramp-parse-rhosts "/etc/hosts.equiv") | |
1168 | (tramp-parse-rhosts "~/.rhosts")) | |
1169 | @end example | |
1170 | @end defun | |
1171 | ||
1172 | @defun tramp-set-completion-function method function-list | |
1173 | This function sets @var{function-list} as list of completion functions | |
6b61353c | 1174 | for @var{method}. |
16674e4f KG |
1175 | |
1176 | Example: | |
1177 | @example | |
1178 | (tramp-set-completion-function "ssh" | |
18d6d595 KG |
1179 | '((tramp-parse-sconfig "/etc/ssh_config") |
1180 | (tramp-parse-sconfig "~/.ssh/config"))) | |
16674e4f | 1181 | |
18d6d595 KG |
1182 | @result{} ((tramp-parse-sconfig "/etc/ssh_config") |
1183 | (tramp-parse-sconfig "~/.ssh/config")) | |
16674e4f KG |
1184 | @end example |
1185 | @end defun | |
1186 | ||
18d6d595 | 1187 | The following predefined functions parsing configuration files exist: |
16674e4f KG |
1188 | |
1189 | @table @asis | |
1190 | @item @code{tramp-parse-rhosts} | |
1191 | @findex tramp-parse-rhosts | |
1192 | ||
1193 | This function parses files which are syntactical equivalent to | |
1194 | @file{~/.rhosts}. It returns both host names and user names, if | |
1195 | specified. | |
1196 | ||
1197 | @item @code{tramp-parse-shosts} | |
1198 | @findex tramp-parse-shosts | |
1199 | ||
1200 | This function parses files which are syntactical equivalent to | |
18d6d595 | 1201 | @file{~/.ssh/known_hosts}. Since there are no user names specified |
16674e4f KG |
1202 | in such files, it can return host names only. |
1203 | ||
18d6d595 KG |
1204 | @item @code{tramp-parse-sconfig} |
1205 | @findex tramp-parse-shosts | |
1206 | ||
41bed43c | 1207 | This function returns the host nicknames defined by @code{Host} entries |
18d6d595 KG |
1208 | in @file{~/.ssh/config} style files. |
1209 | ||
6b61353c KH |
1210 | @item @code{tramp-parse-shostkeys} |
1211 | @findex tramp-parse-shostkeys | |
1212 | ||
1213 | SSH2 parsing of directories @file{/etc/ssh2/hostkeys/*} and | |
1214 | @file{~/ssh2/hostkeys/*}. Hosts are coded in file names | |
1215 | @file{hostkey_PORTNUMBER_HOST-NAME.pub}. User names are always nil. | |
1216 | ||
1217 | @item @code{tramp-parse-sknownhosts} | |
1218 | @findex tramp-parse-shostkeys | |
1219 | ||
1220 | Another SSH2 style parsing of directories like | |
1221 | @file{/etc/ssh2/knownhosts/*} and @file{~/ssh2/knownhosts/*}. This | |
1222 | case, hosts names are coded in file names | |
1223 | @file{HOST-NAME.ALGORITHM.pub}. User names are always nil. | |
1224 | ||
16674e4f KG |
1225 | @item @code{tramp-parse-hosts} |
1226 | @findex tramp-parse-hosts | |
1227 | ||
1228 | A function dedicated to @file{/etc/hosts} style files. It returns | |
1229 | host names only. | |
1230 | ||
1231 | @item @code{tramp-parse-passwd} | |
1232 | @findex tramp-parse-passwd | |
1233 | ||
292ffc15 KG |
1234 | A function which parses @file{/etc/passwd} like files. Obviously, it |
1235 | can return user names only. | |
16674e4f | 1236 | |
292ffc15 KG |
1237 | @item @code{tramp-parse-netrc} |
1238 | @findex tramp-parse-netrc | |
1239 | ||
1240 | Finally, a function which parses @file{~/.netrc} like files. | |
1241 | @end table | |
16674e4f KG |
1242 | |
1243 | If you want to keep your own data in a file, with your own structure, | |
1244 | you might provide such a function as well. This function must meet | |
1245 | the following conventions: | |
1246 | ||
1247 | @defun my-tramp-parse file | |
1248 | @var{file} must be either a file name on your host, or @code{nil}. The | |
1249 | function must return a list of (@var{user} @var{host}), which are | |
1250 | taken as candidates for user and host name completion. | |
1251 | ||
1252 | Example: | |
1253 | @example | |
1254 | (my-tramp-parse "~/.my-tramp-hosts") | |
1255 | ||
1256 | @result{} ((nil "toto") ("daniel" "melancholia")) | |
1257 | @end example | |
1258 | @end defun | |
1259 | ||
1260 | ||
6b61353c KH |
1261 | @node Password caching |
1262 | @section Reusing passwords for several connections. | |
1263 | @cindex passwords | |
1264 | ||
1265 | Sometimes it is necessary to connect to the same remote host several | |
1266 | times. Reentering passwords again and again would be annoying, when | |
1267 | the choosen method does not support access without password prompt | |
1268 | throught own configuration. | |
1269 | ||
1270 | By default, @tramp{} caches the passwords entered by you. They will | |
1271 | be reused next time if a connection needs them for the same user name | |
1272 | and host name, independant of the connection method. | |
1273 | ||
1274 | @vindex password-cache-expiry | |
1275 | Passwords are not saved permanently, that means the password caching | |
1276 | is limited to the lifetime of your @value{emacs-name} session. You | |
1277 | can influence the lifetime of password caching by customizing the | |
1278 | variable @code{password-cache-expiry}. The value is the number of | |
1279 | seconds how long passwords are cached. Setting it to @code{nil} | |
1280 | disables the expiration. | |
1281 | ||
1282 | @findex tramp-clear-passwd | |
1283 | A password is removed from the cache if a connection isn't established | |
1284 | successfully. You can remove a password from the cache also by | |
1285 | executing @kbd{M-x tramp-clear-passwd} in a buffer containing a | |
1286 | related remote file or directory. | |
1287 | ||
1288 | @vindex password-cache | |
1289 | If you don't like this feature for security reasons, password caching | |
1290 | can be disabled totally by customizing the variable | |
1291 | @code{password-cache} (setting it to @code{nil}). | |
1292 | ||
1293 | Implementation Note: password caching is based on the package | |
1294 | password.el in No Gnus. For the time being, it is activated only when | |
1295 | this package is seen in the @code{load-path} while loading @tramp{}. | |
1296 | @ifset tramp-inst | |
1297 | If you don't use No Gnus, you can take password.el from the @tramp{} | |
1298 | @file{contrib} directory, see @ref{Installation parameters}. | |
1299 | @end ifset | |
1300 | It will be activated mandatory once No Gnus has found its way into | |
1301 | @value{emacs-name}. | |
1302 | ||
1303 | ||
fb7933a3 KG |
1304 | @node Remote Programs |
1305 | @section How @tramp{} finds and uses programs on the remote machine. | |
1306 | ||
1307 | @tramp{} depends on a number of programs on the remote host in order to | |
1308 | function, including @command{ls}, @command{test}, @command{find} and | |
1309 | @command{cat}. | |
1310 | ||
1311 | In addition to these required tools, there are various tools that may be | |
1312 | required based on the connection method. See @ref{Inline methods} and | |
1313 | @ref{External transfer methods} for details on these. | |
1314 | ||
1315 | Certain other tools, such as @command{perl} (or @command{perl5}) and | |
1316 | @command{grep} will be used if they can be found. When they are | |
1317 | available, they are used to improve the performance and accuracy of | |
1318 | remote file access. | |
1319 | ||
92eeeafc | 1320 | @vindex tramp-remote-path |
fb7933a3 KG |
1321 | When @tramp{} connects to the remote machine, it searches for the |
1322 | programs that it can use. The variable @var{tramp-remote-path} controls | |
1323 | the directories searched on the remote machine. | |
1324 | ||
1325 | By default, this is set to a reasonable set of defaults for most | |
1326 | machines. It is possible, however, that your local (or remote ;) system | |
1327 | administrator has put the tools you want in some obscure local | |
1328 | directory. | |
1329 | ||
1330 | In this case, you can still use them with @tramp{}. You simply need to | |
1331 | add code to your @file{.emacs} to add the directory to the remote path. | |
1332 | This will then be searched by @tramp{} when you connect and the software | |
1333 | found. | |
1334 | ||
1335 | To add a directory to the remote search path, you could use code such | |
1336 | as: | |
1337 | ||
16674e4f KG |
1338 | @lisp |
1339 | @i{;; We load @tramp{} to define the variable.} | |
1340 | (require 'tramp) | |
1341 | @i{;; We have @command{perl} in "/usr/local/perl/bin"} | |
92eeeafc | 1342 | (add-to-list 'tramp-remote-path "/usr/local/perl/bin") |
16674e4f KG |
1343 | @end lisp |
1344 | ||
fb7933a3 KG |
1345 | |
1346 | @node Remote shell setup | |
1347 | @comment node-name, next, previous, up | |
1348 | @section Remote shell setup hints | |
92eeeafc | 1349 | @cindex remote shell setup |
e28e4d20 KG |
1350 | @cindex @file{.profile} file |
1351 | @cindex @file{.login} file | |
92eeeafc | 1352 | @cindex shell init files |
fb7933a3 KG |
1353 | |
1354 | As explained in the @ref{Overview} section, @tramp{} connects to the | |
1355 | remote host and talks to the shell it finds there. Of course, when you | |
1356 | log in, the shell executes its init files. Suppose your init file | |
16674e4f | 1357 | requires you to enter the birth date of your mother; clearly @tramp{} |
fb7933a3 KG |
1358 | does not know this and hence fails to log you in to that host. |
1359 | ||
1360 | There are different possible strategies for pursuing this problem. One | |
1361 | strategy is to enable @tramp{} to deal with all possible situations. | |
1362 | This is a losing battle, since it is not possible to deal with | |
1363 | @emph{all} situations. The other strategy is to require you to set up | |
6b61353c | 1364 | the remote host such that it behaves like @tramp{} expects. This might |
fb7933a3 KG |
1365 | be inconvenient because you have to invest a lot of effort into shell |
1366 | setup before you can begin to use @tramp{}. | |
1367 | ||
1368 | The package, therefore, pursues a combined approach. It tries to figure | |
1369 | out some of the more common setups, and only requires you to avoid | |
1370 | really exotic stuff. For example, it looks through a list of | |
1371 | directories to find some programs on the remote host. And also, it | |
abc6be8d | 1372 | knows that it is not obvious how to check whether a file exists, and |
fb7933a3 KG |
1373 | therefore it tries different possibilities. (On some hosts and shells, |
1374 | the command @code{test -e} does the trick, on some hosts the shell | |
1375 | builtin doesn't work but the program @code{/usr/bin/test -e} or | |
1376 | @code{/bin/test -e} works. And on still other hosts, @code{ls -d} is | |
1377 | the right way to do this.) | |
1378 | ||
1379 | Below you find a discussion of a few things that @tramp{} does not deal | |
1380 | with, and that you therefore have to set up correctly. | |
1381 | ||
92eeeafc KG |
1382 | @table @asis |
1383 | @item @var{shell-prompt-pattern} | |
fb7933a3 | 1384 | @vindex shell-prompt-pattern |
92eeeafc | 1385 | |
fb7933a3 KG |
1386 | After logging in to the remote host, @tramp{} has to wait for the remote |
1387 | shell startup to finish before it can send commands to the remote | |
1388 | shell. The strategy here is to wait for the shell prompt. In order to | |
1389 | recognize the shell prompt, the variable @code{shell-prompt-pattern} has | |
1390 | to be set correctly to recognize the shell prompt on the remote host. | |
1391 | ||
abc6be8d KG |
1392 | Note that @tramp{} requires the match for @code{shell-prompt-pattern} |
1393 | to be at the end of the buffer. Many people have something like the | |
83fa16cf | 1394 | following as the value for the variable: @code{"^[^>$][>$] *"}. Now |
abc6be8d KG |
1395 | suppose your shell prompt is @code{a <b> c $ }. In this case, |
1396 | @tramp{} recognizes the @code{>} character as the end of the prompt, | |
1397 | but it is not at the end of the buffer. | |
83fa16cf | 1398 | |
16674e4f KG |
1399 | @item @var{tramp-shell-prompt-pattern} |
1400 | @vindex tramp-shell-prompt-pattern | |
1401 | ||
1402 | This regular expression is used by @tramp{} in the same way as | |
1403 | @code{shell-prompt-pattern}, to match prompts from the remote shell. | |
1404 | This second variable exists because the prompt from the remote shell | |
1405 | might be different from the prompt from a local shell --- after all, | |
1406 | the whole point of @tramp{} is to log in to remote hosts as a | |
1407 | different user. The default value of | |
1408 | @code{tramp-shell-prompt-pattern} is the same as the default value of | |
1409 | @code{shell-prompt-pattern}, which is reported to work well in many | |
1410 | circumstances. | |
1411 | ||
fb7933a3 | 1412 | @item @code{tset} and other questions |
92eeeafc KG |
1413 | @cindex Unix command tset |
1414 | @cindex tset Unix command | |
fb7933a3 KG |
1415 | |
1416 | Some people invoke the @code{tset} program from their shell startup | |
16674e4f KG |
1417 | scripts which asks the user about the terminal type of the shell. |
1418 | Maybe some shells ask other questions when they are started. @tramp{} | |
1419 | does not know how to answer these questions. There are two approaches | |
1420 | for dealing with this problem. One approach is to take care that the | |
1421 | shell does not ask any questions when invoked from @tramp{}. You can | |
1422 | do this by checking the @code{TERM} environment variable, it will be | |
1423 | set to @code{dumb} when connecting. | |
fb7933a3 KG |
1424 | |
1425 | @vindex tramp-terminal-type | |
1426 | The variable @code{tramp-terminal-type} can be used to change this value | |
16674e4f KG |
1427 | to @code{dumb}. |
1428 | ||
1429 | The other approach is to teach @tramp{} about these questions. See | |
1430 | the variables @code{tramp-actions-before-shell} and | |
1431 | @code{tramp-multi-actions} (for multi-hop connections). | |
fb7933a3 | 1432 | |
6b61353c KH |
1433 | |
1434 | @item Environment variables named like users in @file{.profile} | |
1435 | ||
1436 | If you have a user named frumple and set the variable @code{FRUMPLE} in | |
1437 | your shell environment, then this might cause trouble. Maybe rename | |
1438 | the variable to @code{FRUMPLE_DIR} or the like. | |
1439 | ||
1440 | This weird effect was actually reported by a @tramp{} user! | |
1441 | ||
1442 | ||
6013ce47 KG |
1443 | @item Non-Bourne commands in @file{.profile} |
1444 | ||
1445 | After logging in to the remote host, @tramp{} issues the command | |
1446 | @code{exec /bin/sh}. (Actually, the command is slightly different.) | |
1447 | When @code{/bin/sh} is executed, it reads some init files, such as | |
1448 | @file{~/.shrc} or @file{~/.profile}. | |
1449 | ||
1450 | Now, some people have a login shell which is not @code{/bin/sh} but a | |
1451 | Bourne-ish shell such as bash or ksh. Some of these people might put | |
1452 | their shell setup into the files @code{~/.shrc} or @code{~/.profile}. | |
1453 | This way, it is possible for non-Bourne constructs to end up in those | |
1454 | files. Then, @code{exec /bin/sh} might cause the Bourne shell to barf | |
1455 | on those constructs. | |
1456 | ||
1457 | As an example, imagine somebody putting @code{export FOO=bar} into the | |
1458 | file @file{~/.profile}. The standard Bourne shell does not understand | |
1459 | this syntax and will emit a syntax error when it reaches this line. | |
1460 | ||
1461 | Another example is the tilde (@code{~}) character, say when adding | |
1462 | @file{~/bin} to @code{$PATH}. Many Bourne shells will not expand this | |
1463 | character, and since there is usually no directory whose name consists | |
1464 | of the single character tilde, strange things will happen. | |
1465 | ||
1466 | What can you do about this? | |
1467 | ||
1468 | Well, one possibility is to make sure that everything in @file{~/.shrc} | |
1469 | and @file{~/.profile} on all remote hosts is Bourne-compatible. In the | |
1470 | above example, instead of @code{export FOO=bar}, you might use | |
1471 | @code{FOO=bar; export FOO} instead. | |
1472 | ||
1473 | The other possibility is to put your non-Bourne shell setup into some | |
1474 | other files. For example, bash reads the file @file{~/.bash_profile} | |
1475 | instead of @file{~/.profile}, if the former exists. So bash | |
1476 | aficionados just rename their @file{~/.profile} to | |
1477 | @file{~/.bash_profile} on all remote hosts, and Bob's your uncle. | |
1478 | ||
1479 | The @tramp{} developers would like to circumvent this problem, so if you | |
1480 | have an idea about it, please tell us. However, we are afraid it is not | |
1481 | that simple: before saying @code{exec /bin/sh}, @tramp{} does not know | |
1482 | which kind of shell it might be talking to. It could be a Bourne-ish | |
1483 | shell like ksh or bash, or it could be a csh derivative like tcsh, or | |
1484 | it could be zsh, or even rc. If the shell is Bourne-ish already, then | |
1485 | it might be prudent to omit the @code{exec /bin/sh} step. But how to | |
1486 | find out if the shell is Bourne-ish? | |
1487 | ||
92eeeafc | 1488 | @end table |
fb7933a3 KG |
1489 | |
1490 | ||
b1a2b924 KG |
1491 | @node Auto-save and Backup |
1492 | @section Auto-save and Backup configuration | |
1493 | @cindex auto-save | |
1494 | @cindex backup | |
1495 | @vindex backup-directory-alist | |
1496 | ||
6b61353c KH |
1497 | Normally, @value{emacs-name} writes backup files to the same directory |
1498 | as the original files, but this behavior can be changed via the | |
1499 | variable @code{backup-directory-alist}. In connection with @tramp{}, | |
1500 | this can have unexpected side effects. Suppose that you specify that | |
1501 | all backups should go to the directory @file{~/.emacs.d/backups/}, and | |
1502 | then you edit the file @file{/su:root@@localhost:/etc/secretfile}. | |
1503 | The effect is that the backup file will be owned by you and not by | |
1504 | root, thus possibly enabling others to see it even if they were not | |
1505 | intended to see it. | |
b1a2b924 KG |
1506 | |
1507 | When @code{backup-directory-alist} is nil (the default), such problems | |
1508 | do not occur. | |
1509 | ||
1510 | If you wish to customize the variable, the workaround is to include | |
6b61353c | 1511 | special settings for @tramp{} files. For example, the following statement |
b1a2b924 KG |
1512 | effectively `turns off' the effect of @code{backup-directory-alist} for |
1513 | @tramp{} files: | |
1514 | ||
1515 | @lisp | |
1516 | (require 'tramp) | |
1517 | (add-to-list 'backup-directory-alist | |
1518 | (cons tramp-file-name-regexp nil)) | |
1519 | @end lisp | |
1520 | ||
6b61353c KH |
1521 | The same problem can happen with auto-saving files. |
1522 | @ifset emacs | |
1523 | Since @value{emacs-name} 21, the variable | |
1524 | @code{auto-save-file-name-transforms} keeps information, on which | |
1525 | directory an auto-saved file should go. By default, it is initialized | |
1526 | for @tramp{} files to the local temporary directory. | |
1527 | ||
1528 | On some versions of @value{emacs-name}, namely the version built for | |
1529 | Debian Linux, the variable @code{auto-save-file-name-transforms} | |
1530 | contains the directory where @value{emacs-name} was built. A | |
1531 | workaround is to manually set the variable to a sane value. | |
1532 | ||
1533 | If auto-saved files should go into the same directory as the original | |
1534 | files, @code{auto-save-file-name-transforms} should be set to nil. | |
1535 | ||
1536 | Another possibility is to set the variable | |
1537 | @code{tramp-auto-save-directory} to a proper value. | |
1538 | @end ifset | |
1539 | @ifset xemacs | |
1540 | For this purpose you can set the variable | |
1541 | @code{tramp-auto-save-directory} to a proper value. | |
1542 | @end ifset | |
1543 | ||
b1a2b924 | 1544 | |
fb7933a3 KG |
1545 | @node Windows setup hints |
1546 | @section Issues with Cygwin ssh | |
e28e4d20 | 1547 | @cindex Cygwin, issues |
fb7933a3 KG |
1548 | |
1549 | This section needs a lot of work! Please help. | |
1550 | ||
abc6be8d KG |
1551 | @cindex method sshx with Cygwin |
1552 | @cindex sshx method with Cygwin | |
fb7933a3 KG |
1553 | If you use the Cygwin installation of ssh (you have to explicitly select |
1554 | it in the installer), then it should work out of the box to just select | |
abc6be8d | 1555 | @code{sshx} as the connection method. You can find information about |
fb7933a3 KG |
1556 | setting up Cygwin in their FAQ at @uref{http://cygwin.com/faq/}. |
1557 | ||
abc6be8d KG |
1558 | @cindex method scpx with Cygwin |
1559 | @cindex scpx method with Cygwin | |
1560 | If you wish to use the @code{scpx} connection method, then you might | |
6b61353c KH |
1561 | have the problem that @value{emacs-name} calls @code{scp} with a |
1562 | Windows filename such as @code{c:/foo}. The Cygwin version of | |
1563 | @code{scp} does not know about Windows filenames and interprets this | |
1564 | as a remote filename on the host @code{c}. | |
abc6be8d KG |
1565 | |
1566 | One possible workaround is to write a wrapper script for @code{scp} | |
1567 | which converts the Windows filename to a Cygwinized filename. | |
1568 | ||
6b61353c KH |
1569 | I guess that another workaround is to run @value{emacs-name} under |
1570 | Cygwin, or to run a Cygwinized @value{emacs-name}. | |
abc6be8d KG |
1571 | |
1572 | @cindex Cygwin and ssh-agent | |
6b61353c | 1573 | @cindex SSH_AUTH_SOCK and @value{emacs-name} on Windows |
abc6be8d KG |
1574 | If you want to use either @code{ssh} based method on Windows, then you |
1575 | might encounter problems with @code{ssh-agent}. Using this program, | |
1576 | you can avoid typing the pass-phrase every time you log in (and the | |
1577 | @code{scpx} method more or less requires you to use @code{ssh-agent} | |
1578 | because it does not allow you to type a password or pass-phrase). | |
6b61353c KH |
1579 | However, if you start @value{emacs-name} from a desktop shortcut, then |
1580 | the environment variable @code{SSH_AUTH_SOCK} is not set and so | |
1581 | @value{emacs-name} and thus @tramp{} and thus @code{ssh} and | |
1582 | @code{scp} started from @tramp{} cannot communicate with | |
1583 | @code{ssh-agent}. It works better to start @value{emacs-name} from | |
1584 | the shell. | |
abc6be8d KG |
1585 | |
1586 | If anyone knows how to start @code{ssh-agent} under Windows in such a | |
1587 | way that desktop shortcuts can profit, please holler. I don't really | |
1588 | know anything at all about Windows@dots{} | |
1589 | ||
fb7933a3 KG |
1590 | |
1591 | @node Usage | |
6b61353c KH |
1592 | @chapter Using @tramp{} |
1593 | @cindex using @tramp{} | |
fb7933a3 KG |
1594 | |
1595 | Once you have installed @tramp{} it will operate fairly transparently. You | |
1596 | will be able to access files on any remote machine that you can log in | |
1597 | to as though they were local. | |
1598 | ||
1599 | Files are specified to @tramp{} using a formalized syntax specifying the | |
92eeeafc | 1600 | details of the system to connect to. This is similar to the syntax used |
16674e4f KG |
1601 | by the @value{ftp-package-name} package. |
1602 | ||
1603 | @cindex type-ahead | |
6b61353c KH |
1604 | Something that might happen which surprises you is that |
1605 | @value{emacs-name} remembers all your keystrokes, so if you see a | |
1606 | password prompt from @value{emacs-name}, say, and hit @kbd{@key{RET}} | |
1607 | twice instead of once, then the second keystroke will be processed by | |
1608 | @value{emacs-name} after @tramp{} has done its thing. Why, this | |
1609 | type-ahead is normal behavior, you say. Right you are, but be aware | |
1610 | that opening a remote file might take quite a while, maybe half a | |
1611 | minute when a connection needs to be opened. Maybe after half a | |
1612 | minute you have already forgotten that you hit that key! | |
fb7933a3 KG |
1613 | |
1614 | @menu | |
1615 | * Filename Syntax:: @tramp{} filename conventions. | |
16674e4f KG |
1616 | * Multi-hop filename syntax:: Multi-hop filename conventions. |
1617 | * Filename completion:: Filename completion. | |
1618 | * Dired:: Dired. | |
fb7933a3 KG |
1619 | @end menu |
1620 | ||
1621 | ||
1622 | @node Filename Syntax | |
1623 | @section @tramp{} filename conventions | |
92eeeafc KG |
1624 | @cindex filename syntax |
1625 | @cindex filename examples | |
fb7933a3 | 1626 | |
884b79ec | 1627 | To access the file @var{localname} on the remote machine @var{machine} you |
16674e4f | 1628 | would specify the filename |
884b79ec | 1629 | @file{@value{tramp-prefix}@var{machine}@value{tramp-postfix}@var{localname}}. |
16674e4f KG |
1630 | This will connect to @var{machine} and transfer the file using the |
1631 | default method. @xref{Default Method}. | |
fb7933a3 | 1632 | |
16674e4f | 1633 | Some examples of @tramp{} filenames are shown below. |
fb7933a3 KG |
1634 | |
1635 | @table @file | |
16674e4f | 1636 | @item @value{tramp-prefix}melancholia@value{tramp-postfix}.emacs |
fb7933a3 KG |
1637 | Edit the file @file{.emacs} in your home directory on the machine |
1638 | @code{melancholia}. | |
1639 | ||
16674e4f | 1640 | @item @value{tramp-prefix}melancholia.danann.net@value{tramp-postfix}.emacs |
fb7933a3 KG |
1641 | This edits the same file, using the fully qualified domain name of |
1642 | the machine. | |
1643 | ||
16674e4f | 1644 | @item @value{tramp-prefix}melancholia@value{tramp-postfix}~/.emacs |
fb7933a3 KG |
1645 | This also edits the same file --- the @file{~} is expanded to your |
1646 | home directory on the remote machine, just like it is locally. | |
1647 | ||
16674e4f | 1648 | @item @value{tramp-prefix}melancholia@value{tramp-postfix}~daniel/.emacs |
fb7933a3 KG |
1649 | This edits the file @file{.emacs} in the home directory of the user |
1650 | @code{daniel} on the machine @code{melancholia}. The @file{~<user>} | |
1651 | construct is expanded to the home directory of that user on the remote | |
1652 | machine. | |
1653 | ||
16674e4f | 1654 | @item @value{tramp-prefix}melancholia@value{tramp-postfix}/etc/squid.conf |
fb7933a3 KG |
1655 | This edits the file @file{/etc/squid.conf} on the machine |
1656 | @code{melancholia}. | |
1657 | ||
1658 | @end table | |
1659 | ||
16674e4f KG |
1660 | Unless you specify a different name to use, @tramp{} will use the |
1661 | current local user name as the remote user name to log in with. If you | |
1662 | need to log in as a different user, you can specify the user name as | |
1663 | part of the filename. | |
fb7933a3 | 1664 | |
16674e4f KG |
1665 | To log in to the remote machine as a specific user, you use the syntax |
1666 | @file{@value{tramp-prefix}@var{user}@@@var{machine}@value{tramp-postfix}/@var{path/to.file}}. | |
1667 | That means that connecting to @code{melancholia} as @code{daniel} and | |
f37fc5a7 | 1668 | editing @file{.emacs} in your home directory you would specify |
16674e4f | 1669 | @file{@value{tramp-prefix}daniel@@melancholia@value{tramp-postfix}.emacs}. |
fb7933a3 KG |
1670 | |
1671 | It is also possible to specify other file transfer methods | |
16674e4f KG |
1672 | (@pxref{Default Method}) as part of the filename. |
1673 | @ifset emacs | |
1674 | This is done by putting the method before the user and host name, as | |
1675 | in | |
1676 | @file{@value{tramp-prefix}@var{method}@value{tramp-postfix-single-hop}} | |
abc6be8d | 1677 | (Note the trailing colon). |
16674e4f KG |
1678 | @end ifset |
1679 | @ifset xemacs | |
1680 | This is done by replacing the initial | |
1681 | @file{@value{tramp-prefix}} with | |
1682 | @file{@value{tramp-prefix}<method>@value{tramp-postfix-single-hop}}. | |
1683 | (Note the trailing slash!). | |
1684 | @end ifset | |
1685 | The user, machine and file specification remain the same. | |
fb7933a3 | 1686 | |
f37fc5a7 | 1687 | So, to connect to the machine @code{melancholia} as @code{daniel}, |
6b61353c | 1688 | using the @option{ssh} method to transfer files, and edit @file{.emacs} |
f37fc5a7 | 1689 | in my home directory I would specify the filename |
6b61353c | 1690 | @file{@value{tramp-prefix}ssh@value{tramp-postfix-single-hop}daniel@@melancholia@value{tramp-postfix}.emacs}. |
fb7933a3 KG |
1691 | |
1692 | ||
1693 | @node Multi-hop filename syntax | |
1694 | @section Multi-hop filename conventions | |
92eeeafc KG |
1695 | @cindex filename syntax for multi-hop files |
1696 | @cindex multi-hop filename syntax | |
fb7933a3 KG |
1697 | |
1698 | The syntax of multi-hop file names is necessarily slightly different | |
16674e4f | 1699 | than the syntax of other @tramp{} file names. Here's an example |
6b61353c | 1700 | multi-hop file name: |
fb7933a3 | 1701 | |
16674e4f KG |
1702 | @example |
1703 | @value{tramp-prefix}multi@value{tramp-postfix-single-hop}rsh@value{tramp-postfix-multi-hop}out@@gate@value{tramp-postfix-single-hop}telnet@value{tramp-postfix-multi-hop}kai@@real.host@value{tramp-postfix}/path/to.file | |
1704 | @end example | |
fb7933a3 KG |
1705 | |
1706 | This is quite a mouthful. So let's go through it step by step. The | |
16674e4f KG |
1707 | file name consists of three parts. |
1708 | @ifset emacs | |
1709 | The parts are separated by colons | |
1710 | @end ifset | |
1711 | @ifset xemacs | |
1712 | The parts are separated by slashes and square brackets. | |
1713 | @end ifset | |
1714 | The first part is @file{@value{tramp-prefix}multi}, the method | |
1715 | specification. The second part is | |
1716 | @file{rsh@value{tramp-postfix-multi-hop}out@@gate@value{tramp-postfix-single-hop}telnet@value{tramp-postfix-multi-hop}kai@@real.host} | |
1717 | and specifies the hops. The final part is @file{/path/to.file} and | |
1718 | specifies the file name on the remote host. | |
fb7933a3 | 1719 | |
abc6be8d | 1720 | The first part and the final part should be clear. See @ref{Multi-hop |
fb7933a3 KG |
1721 | Methods}, for a list of alternatives for the method specification. |
1722 | ||
16674e4f KG |
1723 | The second part can be subdivided again into components, so-called |
1724 | hops. In the above file name, there are two hops, | |
1725 | @file{rsh@value{tramp-postfix-multi-hop}out@@gate} and | |
1726 | @file{telnet@value{tramp-postfix-multi-hop}kai@@real.host}. | |
fb7933a3 KG |
1727 | |
1728 | Each hop can @emph{again} be subdivided into (three) components, the | |
1729 | @dfn{hop method}, the @dfn{user name} and the @dfn{host name}. The | |
1730 | meaning of the second and third component should be clear, and the hop | |
1731 | method says what program to use to perform that hop. | |
1732 | ||
16674e4f KG |
1733 | The first hop, @file{rsh@value{tramp-postfix-multi-hop}out@@gate}, |
1734 | says to use @command{rsh} to log in as user @code{out} to the host | |
1735 | @code{gate}. Starting at that host, the second hop, | |
1736 | @file{telnet@value{tramp-postfix-multi-hop}kai@@real.host}, says to | |
1737 | use @command{telnet} to log in as user @code{kai} to host | |
1738 | @code{real.host}. | |
1739 | ||
1740 | @xref{Multi-hop Methods}, for a list of possible hop method values. | |
1741 | The variable @code{tramp-multi-connection-function-alist} contains the | |
1742 | list of possible hop methods and information on how to execute them, | |
1743 | should you want to add your own. | |
fb7933a3 | 1744 | |
16674e4f KG |
1745 | |
1746 | @node Filename completion | |
1747 | @section Filename completion | |
1748 | @cindex filename completion | |
1749 | ||
1750 | Filename completion works with @tramp{} for both completing methods, | |
1751 | user names and machine names (except multi hop methods) as well as for | |
1752 | files on remote machines. | |
1753 | ||
1754 | If you, for example, type @kbd{C-x C-f @value{tramp-prefix}t | |
1755 | @key{TAB}}, @tramp{} might give you as result the choice for | |
1756 | ||
1757 | @example | |
1758 | @ifset emacs | |
1759 | @value{tramp-prefix-single-hop}telnet@value{tramp-postfix-single-hop} tmp/ | |
1760 | @value{tramp-prefix-single-hop}toto@value{tramp-postfix} | |
1761 | @end ifset | |
1762 | @ifset xemacs | |
1763 | @value{tramp-prefix-single-hop}telnet@value{tramp-postfix-single-hop} @value{tramp-prefix-single-hop}toto@value{tramp-postfix} | |
1764 | @end ifset | |
1765 | @end example | |
177c0ea7 | 1766 | |
16674e4f KG |
1767 | @samp{@value{tramp-prefix-single-hop}telnet@value{tramp-postfix-single-hop}} |
1768 | is a possible completion for the respective method, | |
1769 | @ifset emacs | |
1770 | @samp{tmp/} stands for the directory @file{/tmp} on your local | |
1771 | machine, | |
1772 | @end ifset | |
1773 | and @samp{@value{tramp-prefix-single-hop}toto@value{tramp-postfix}} | |
6b61353c | 1774 | might be a host @tramp{} has detected in your @file{~/.ssh/known_hosts} |
16674e4f KG |
1775 | file (given you're using default method @option{ssh}). |
1776 | ||
1777 | If you go on to type @kbd{e @key{TAB}}, the minibuffer is completed to | |
1778 | @samp{@value{tramp-prefix}telnet@value{tramp-postfix-single-hop}}. | |
1779 | Next @kbd{@key{TAB}} brings you all machine names @tramp{} detects in | |
1780 | your @file{/etc/hosts} file, let's say | |
1781 | ||
1782 | @example | |
1783 | @value{tramp-prefix-single-hop}telnet@value{tramp-postfix-single-hop}127.0.0.1@value{tramp-postfix} @value{tramp-prefix-single-hop}telnet@value{tramp-postfix-single-hop}192.168.0.1@value{tramp-postfix} | |
1784 | @value{tramp-prefix-single-hop}telnet@value{tramp-postfix-single-hop}localhost@value{tramp-postfix} @value{tramp-prefix-single-hop}telnet@value{tramp-postfix-single-hop}melancholia.danann.net@value{tramp-postfix} | |
1785 | @value{tramp-prefix-single-hop}telnet@value{tramp-postfix-single-hop}melancholia@value{tramp-postfix} | |
1786 | @end example | |
1787 | ||
1788 | Now you can choose the desired machine, and you can continue to | |
1789 | complete file names on that machine. | |
1790 | ||
1791 | As filename completion needs to fetch the listing of files from the | |
1792 | remote machine, this feature is sometimes fairly slow. As @tramp{} | |
1793 | does not yet cache the results of directory listing, there is no gain | |
1794 | in performance the second time you complete filenames. | |
1795 | ||
1796 | If the configuration files (@pxref{Customizing Completion}), which | |
1797 | @tramp{} uses for analysis of completion, offer user names, those user | |
1798 | names will be taken into account as well. | |
fb7933a3 KG |
1799 | |
1800 | ||
1801 | @node Dired | |
16674e4f | 1802 | @section Dired |
92eeeafc | 1803 | @cindex dired |
fb7933a3 KG |
1804 | |
1805 | @tramp{} works transparently with dired, enabling you to use this powerful | |
1806 | file management tool to manage files on any machine you have access to | |
1807 | over the Internet. | |
1808 | ||
fb7933a3 | 1809 | If you need to browse a directory tree, Dired is a better choice, at |
92eeeafc | 1810 | present, than filename completion. Dired has its own cache mechanism |
fb7933a3 KG |
1811 | and will only fetch the directory listing once. |
1812 | ||
1813 | ||
1814 | @node Bug Reports | |
1815 | @chapter Reporting Bugs and Problems | |
92eeeafc | 1816 | @cindex bug reports |
fb7933a3 KG |
1817 | |
1818 | Bugs and problems with @tramp{} are actively worked on by the development | |
1819 | team. Feature requests and suggestions are also more than welcome. | |
1820 | ||
1821 | The @tramp{} mailing list is a great place to get information on working | |
1822 | with @tramp{}, solving problems and general discussion and advice on topics | |
1823 | relating to the package. | |
1824 | ||
1825 | The mailing list is at @email{tramp-devel@@mail.freesoftware.fsf.org}. | |
1826 | Messages sent to this address go to all the subscribers. This is | |
1827 | @emph{not} the address to send subscription requests to. | |
1828 | ||
1829 | For help on subscribing to the list, send mail to the administrative | |
1830 | address, @email{tramp-devel-request@@mail.freesoftware.fsf.org}, with the | |
1831 | subject @samp{help}. | |
1832 | ||
1833 | To report a bug in @tramp{}, you should execute @kbd{M-x tramp-bug}. This | |
1834 | will automatically generate a buffer with the details of your system and | |
1835 | @tramp{} version. | |
1836 | ||
1837 | When submitting a bug report, please try to describe in excruciating | |
1838 | detail the steps required to reproduce the problem, the setup of the | |
1839 | remote machine and any special conditions that exist. | |
1840 | ||
1841 | If you can identify a minimal test case that reproduces the problem, | |
1842 | include that with your bug report. This will make it much easier for the | |
1843 | development team to analyze and correct the problem. | |
1844 | ||
1845 | @node Frequently Asked Questions | |
1846 | @chapter Frequently Asked Questions | |
92eeeafc KG |
1847 | @cindex frequently asked questions |
1848 | @cindex FAQ | |
fb7933a3 KG |
1849 | |
1850 | @itemize @bullet | |
92eeeafc KG |
1851 | @item |
1852 | Where can I get the latest @tramp{}? | |
fb7933a3 | 1853 | |
16674e4f | 1854 | @tramp{} is available under the URL below. |
fb7933a3 | 1855 | |
16674e4f | 1856 | @noindent |
b1a2b924 | 1857 | @uref{http://savannah.nongnu.org/download/tramp/} |
16674e4f KG |
1858 | |
1859 | @noindent | |
1860 | There is also a Savannah project page. | |
1861 | ||
1862 | @noindent | |
6b61353c | 1863 | @uref{http://savannah.nongnu.org/projects/tramp/} |
fb7933a3 | 1864 | |
92eeeafc KG |
1865 | @item |
1866 | Which systems does it work on? | |
fb7933a3 KG |
1867 | |
1868 | The package has been used successfully on Emacs 20 and Emacs 21, as well | |
1869 | as XEmacs 21. XEmacs 20 is more problematic, see the notes in | |
1870 | @file{tramp.el}. I don't think anybody has really tried it on Emacs 19. | |
1871 | ||
1872 | The package was intended to work on Unix, and it really expects a | |
6b61353c KH |
1873 | Unix-like system on the remote end (except the @option{smb} method), |
1874 | but some people seemed to have some success getting it to work on NT | |
1875 | Emacs. | |
fb7933a3 | 1876 | |
abc6be8d KG |
1877 | There is some informations on @tramp{} on NT at the following URL; |
1878 | many thanks to Joe Stoy for providing the information: | |
fb7933a3 KG |
1879 | @uref{ftp://ftp.comlab.ox.ac.uk/tmp/Joe.Stoy/} |
1880 | ||
1881 | The above mostly contains patches to old ssh versions; Tom Roche has a | |
1882 | Web page with instructions: | |
1883 | @uref{http://www4.ncsu.edu/~tlroche/plinkTramp.html} | |
1884 | ||
1885 | ??? Is the XEmacs info correct? | |
1886 | ||
1887 | ??? Can somebody provide some information for getting it to work on NT | |
1888 | Emacs? I think there was some issue with @command{ssh}? | |
1889 | ||
1890 | ||
92eeeafc | 1891 | @item |
18d6d595 KG |
1892 | I can't stop @value{ftp-package-name} starting with @value{emacs-name} |
1893 | ||
1894 | @ifset emacs | |
1895 | @value{ftp-package-name} is loaded from @tramp{} automatically if you | |
1896 | require a file by the ftp method. Unfortunately, there are some Lisp | |
1897 | packages which make @value{ftp-package-name} file name handlers active. | |
1898 | You can see it applying @kbd{C-h v file-name-handler-alist}: | |
1899 | ||
1900 | @example | |
6b61353c | 1901 | file-name-handler-alist's value is |
18d6d595 KG |
1902 | (("^/[^/:]*\\'" . ange-ftp-completion-hook-function) |
1903 | ("^/[^/:]*[^/:.]:" . ange-ftp-hook-function) | |
1904 | ("^/[^/]*$" . tramp-completion-file-name-handler) | |
1905 | ("\\`/[^/:]+:" . tramp-file-name-handler) | |
1906 | ("\\`/:" . file-name-non-special)) | |
1907 | @end example | |
1908 | ||
1909 | Please try to find out which package is responsible for loading | |
1910 | @value{ftp-package-name}, and raise a bug report. | |
fb7933a3 | 1911 | |
18d6d595 KG |
1912 | A workaround is to require @value{ftp-package-name} before @tramp{} in |
1913 | your @file{~/.emacs}, because @tramp{} cleans up the entries in | |
1914 | @code{file-name-handler-alist}: | |
1915 | ||
1916 | @lisp | |
1917 | ;; @value{ftp-package-name} temporarily required | |
1918 | (require 'ange-ftp) | |
1919 | ;; @tramp{} cleans up @code{file-name-handler-alist} | |
1920 | (require 'tramp) | |
1921 | @end lisp | |
1922 | @end ifset | |
1923 | ||
1924 | @ifset xemacs | |
1925 | Not all the older versions of @tramp{} supported @value{emacs-name} | |
1926 | correctly. The first thing to do is to make sure that you have the | |
1927 | latest version of @tramp{} installed. | |
fb7933a3 KG |
1928 | |
1929 | If you do, please try and find out exactly the conditions required for | |
18d6d595 KG |
1930 | the @value{ftp-package-name} handlers to fire. If you can, putting a |
1931 | breakpoint on @code{efs-ftp-path} and sending in the stack trace along | |
1932 | with your bug report would make it easier for the developers to work out | |
1933 | what is going wrong. | |
1934 | @end ifset | |
fb7933a3 KG |
1935 | |
1936 | ||
92eeeafc KG |
1937 | @item |
1938 | File name completion does not work with @tramp{} | |
fb7933a3 KG |
1939 | |
1940 | When you log in to the remote machine, do you see the output of | |
1941 | @command{ls} in color? If so, this may be the cause of your problems. | |
1942 | ||
1943 | @command{ls} outputs @acronym{ANSI} escape sequences that your terminal | |
18d6d595 | 1944 | emulator interprets to set the colors. These escape sequences will |
fb7933a3 KG |
1945 | confuse @tramp{} however. |
1946 | ||
1947 | In your @file{.bashrc}, @file{.profile} or equivalent on the remote | |
1948 | machine you probably have an alias configured that adds the option | |
1949 | @option{--color=yes} or @option{--color=auto}. | |
1950 | ||
1951 | You should remove that alias and ensure that a new login @emph{does not} | |
18d6d595 | 1952 | display the output of @command{ls} in color. If you still cannot use |
fb7933a3 KG |
1953 | filename completion, report a bug to the @tramp{} developers. |
1954 | ||
1955 | ||
92eeeafc KG |
1956 | @item |
1957 | File name completion does not work in large directories | |
fb7933a3 KG |
1958 | |
1959 | @tramp{} uses globbing for some operations. (Globbing means to use the | |
1960 | shell to expand wildcards such as `*.c'.) This might create long | |
abc6be8d | 1961 | command lines, especially in directories with many files. Some shells |
fb7933a3 KG |
1962 | choke on long command lines, or don't cope well with the globbing |
1963 | itself. | |
1964 | ||
1965 | If you have a large directory on the remote end, you may wish to execute | |
92eeeafc | 1966 | a command like @samp{ls -d * ..?* > /dev/null} and see if it hangs. |
fb7933a3 KG |
1967 | Note that you must first start the right shell, which might be |
1968 | @command{/bin/sh}, @command{ksh} or @command{bash}, depending on which | |
1969 | of those supports tilde expansion. | |
1970 | ||
1971 | ||
92eeeafc KG |
1972 | @item |
1973 | What kinds of systems does @tramp{} work on | |
fb7933a3 KG |
1974 | |
1975 | @tramp{} really expects the remote system to be a Unix-like system. The | |
1976 | local system should preferably be Unix-like, as well, but @tramp{} might | |
1977 | work on NT with some tweaking. | |
1978 | ||
1979 | ||
92eeeafc KG |
1980 | @item |
1981 | How can I get notified when @tramp{} file transfers are complete? | |
fb7933a3 | 1982 | |
6b61353c KH |
1983 | The following snippet can be put in your @file{~/.emacs} file. It |
1984 | makes @value{emacs-name} beep after reading from or writing to the | |
1985 | remote host. | |
fb7933a3 KG |
1986 | |
1987 | @lisp | |
1988 | (defadvice tramp-handle-write-region | |
1989 | (after tramp-write-beep-advice activate) | |
1990 | " make tramp beep after writing a file." | |
1991 | (interactive) | |
1992 | (beep)) | |
1993 | (defadvice tramp-handle-do-copy-or-rename-file | |
1994 | (after tramp-copy-beep-advice activate) | |
1995 | " make tramp beep after copying a file." | |
1996 | (interactive) | |
1997 | (beep)) | |
1998 | (defadvice tramp-handle-insert-file-contents | |
1999 | (after tramp-copy-beep-advice activate) | |
2000 | " make tramp beep after copying a file." | |
2001 | (interactive) | |
2002 | (beep)) | |
2003 | @end lisp | |
2004 | ||
2005 | ||
92eeeafc KG |
2006 | @item |
2007 | There's this @file{~/.sh_history} file on the remote host which keeps | |
2008 | growing and growing. What's that? | |
fb7933a3 KG |
2009 | |
2010 | Sometimes, @tramp{} starts @code{ksh} on the remote host for tilde | |
2011 | expansion. Maybe @code{ksh} saves the history by default. @tramp{} | |
2012 | tries to turn off saving the history, but maybe you have to help. For | |
2013 | example, you could put this in your @file{.kshrc}: | |
2014 | ||
2015 | @example | |
2016 | if [ -f $HOME/.sh_history ] ; then | |
2017 | /bin/rm $HOME/.sh_history | |
2018 | fi | |
2019 | if [ "$@{HISTFILE-unset@}" != "unset" ] ; then | |
2020 | unset HISTFILE | |
2021 | fi | |
2022 | if [ "$@{HISTSIZE-unset@}" != "unset" ] ; then | |
2023 | unset HISTSIZE | |
2024 | fi | |
2025 | @end example | |
2026 | ||
884b79ec KG |
2027 | |
2028 | @item @tramp{} doesn't transfer strings with more than 500 characters | |
2029 | correctly | |
2030 | ||
2031 | On some few systems, the implementation of @code{process-send-string} | |
2032 | seems to be broken for longer strings. This case, you should | |
2033 | customize the variable @code{tramp-chunksize} to 500. For a | |
2034 | description how to determine whether this is necessary see the | |
2035 | documentation of @code{tramp-chunksize}. | |
2036 | ||
fb7933a3 KG |
2037 | @end itemize |
2038 | ||
2039 | ||
2040 | @c For the developer | |
2041 | @node Version Control | |
2042 | @chapter The inner workings of remote version control | |
41bed43c | 2043 | @cindex Version Control |
fb7933a3 | 2044 | |
16674e4f KG |
2045 | Unlike @value{ftp-package-name}, @tramp{} has full shell access to the |
2046 | remote machine. This makes it possible to provide version control for | |
2047 | files accessed under @tramp{}. | |
fb7933a3 KG |
2048 | |
2049 | The actual version control binaries must be installed on the remote | |
2050 | machine, accessible in the directories specified in | |
2051 | @var{tramp-remote-path}. | |
2052 | ||
2053 | This transparent integration with the version control systems is one of | |
2054 | the most valuable features provided by @tramp{}, but it is far from perfect. | |
2055 | Work is ongoing to improve the transparency of the system. | |
2056 | ||
2057 | @menu | |
2058 | * Version Controlled Files:: Determining if a file is under version control. | |
2059 | * Remote Commands:: Executing the version control commands on the remote machine. | |
2060 | * Changed workfiles:: Detecting if the working file has changed. | |
2061 | * Checking out files:: Bringing the workfile out of the repository. | |
16674e4f | 2062 | * Miscellaneous Version Control:: Things related to Version Control that don't fit elsewhere. |
fb7933a3 KG |
2063 | @end menu |
2064 | ||
2065 | ||
2066 | @node Version Controlled Files | |
2067 | @section Determining if a file is under version control | |
2068 | ||
2069 | The VC package uses the existence of on-disk revision control master | |
2070 | files to determine if a given file is under revision control. These file | |
2071 | tests happen on the remote machine through the standard @tramp{} mechanisms. | |
2072 | ||
2073 | ||
2074 | @node Remote Commands | |
2075 | @section Executing the version control commands on the remote machine | |
2076 | ||
2077 | There are no hooks provided by VC to allow intercepting of the version | |
2078 | control command execution. The calls occur through the | |
2079 | @code{call-process} mechanism, a function that is somewhat more | |
2080 | efficient than the @code{shell-command} function but that does not | |
2081 | provide hooks for remote execution of commands. | |
2082 | ||
2083 | To work around this, the functions @code{vc-do-command} and | |
2084 | @code{vc-simple-command} have been advised to intercept requests for | |
2085 | operations on files accessed via @tramp{}. | |
2086 | ||
2087 | In the case of a remote file, the @code{shell-command} interface is | |
2088 | used, with some wrapper code, to provide the same functionality on the | |
6b61353c | 2089 | remote machine as would be seen on the local machine. |
fb7933a3 KG |
2090 | |
2091 | ||
2092 | @node Changed workfiles | |
2093 | @section Detecting if the working file has changed | |
2094 | ||
2095 | As there is currently no way to get access to the mtime of a file on a | |
2096 | remote machine in a portable way, the @code{vc-workfile-unchanged-p} | |
2097 | function is advised to call an @tramp{} specific function for remote files. | |
2098 | ||
2099 | The @code{tramp-vc-workfile-unchanged-p} function uses the functioning VC | |
2100 | diff functionality to determine if any changes have occurred between the | |
2101 | workfile and the version control master. | |
2102 | ||
2103 | This requires that a shell command be executed remotely, a process that | |
2104 | is notably heavier-weight than the mtime comparison used for local | |
2105 | files. Unfortunately, unless a portable solution to the issue is found, | |
2106 | this will remain the cost of remote version control. | |
2107 | ||
2108 | ||
2109 | @node Checking out files | |
2110 | @section Bringing the workfile out of the repository | |
2111 | ||
2112 | VC will, by default, check for remote files and refuse to act on them | |
2113 | when checking out files from the repository. To work around this | |
2114 | problem, the function @code{vc-checkout} knows about @tramp{} files and | |
2115 | allows version control to occur. | |
2116 | ||
2117 | ||
2118 | @node Miscellaneous Version Control | |
2119 | @section Things related to Version Control that don't fit elsewhere | |
2120 | ||
2121 | Minor implementation details, &c. | |
2122 | ||
2123 | @menu | |
2124 | * Remote File Ownership:: How VC determines who owns a workfile. | |
2125 | * Back-end Versions:: How VC determines what release your RCS is. | |
2126 | @end menu | |
2127 | ||
2128 | ||
2129 | @node Remote File Ownership | |
2130 | @subsection How VC determines who owns a workfile | |
2131 | ||
6b61353c KH |
2132 | @value{emacs-name} provides the @code{user-full-name} function to |
2133 | return the login name of the current user as well as mapping from | |
2134 | arbitrary user id values back to login names. The VC code uses this | |
2135 | functionality to map from the uid of the owner of a workfile to the | |
2136 | login name in some circumstances. | |
fb7933a3 KG |
2137 | |
2138 | This will not, for obvious reasons, work if the remote system has a | |
2139 | different set of logins. As such, it is necessary to delegate to the | |
2140 | remote machine the job of determining the login name associated with a | |
2141 | uid. | |
2142 | ||
2143 | Unfortunately, with the profusion of distributed management systems such | |
2144 | as @code{NIS}, @code{NIS+} and @code{NetInfo}, there is no simple, | |
2145 | reliable and portable method for performing this mapping. | |
2146 | ||
2147 | Thankfully, the only place in the VC code that depends on the mapping of | |
2148 | a uid to a login name is the @code{vc-file-owner} function. This returns | |
2149 | the login of the owner of the file as a string. | |
2150 | ||
2151 | This function has been advised to use the output of @command{ls} on the | |
2152 | remote machine to determine the login name, delegating the problem of | |
2153 | mapping the uid to the login to the remote system which should know more | |
2154 | about it than I do. | |
2155 | ||
2156 | ||
2157 | @node Back-end Versions | |
2158 | @subsection How VC determines what release your RCS is | |
2159 | ||
2160 | VC needs to know what release your revision control binaries you are | |
2161 | running as not all features VC supports are available with older | |
2162 | versions of @command{rcs(1)}, @command{cvs(1)} or @command{sccs(1)}. | |
2163 | ||
2164 | The default implementation of VC determines this value the first time it | |
2165 | is needed and then stores the value globally to avoid the overhead of | |
2166 | executing a process and parsing its output each time the information is | |
2167 | needed. | |
2168 | ||
2169 | Unfortunately, life is not quite so easy when remote version control | |
2170 | comes into the picture. Each remote machine may have a different version | |
2171 | of the version control tools and, while this is painful, we need to | |
2172 | ensure that unavailable features are not used remotely. | |
2173 | ||
2174 | To resolve this issue, @tramp{} currently takes the sledgehammer | |
2175 | approach of making the release values of the revision control tools | |
2176 | local to each @tramp{} buffer, forcing VC to determine these values | |
2177 | again each time a new file is visited. | |
2178 | ||
2179 | This has, quite obviously, some performance implications. Thankfully, | |
2180 | most of the common operations performed by VC do not actually require | |
2181 | that the remote version be known. This makes the problem far less | |
2182 | apparent. | |
2183 | ||
2184 | Eventually these values will be captured by @tramp{} on a system by | |
2185 | system basis and the results cached to improve performance. | |
2186 | ||
2187 | ||
884b79ec KG |
2188 | @node Files directories and localnames |
2189 | @chapter How file names, directories and localnames are mangled and managed. | |
fb7933a3 KG |
2190 | |
2191 | @menu | |
884b79ec | 2192 | * Localname deconstruction:: Breaking a localname into its components. |
fb7933a3 KG |
2193 | @end menu |
2194 | ||
2195 | ||
884b79ec KG |
2196 | @node Localname deconstruction |
2197 | @section Breaking a localname into its components. | |
fb7933a3 | 2198 | |
884b79ec | 2199 | @tramp{} file names are somewhat different, obviously, to ordinary file |
fb7933a3 | 2200 | names. As such, the lisp functions @code{file-name-directory} and |
884b79ec KG |
2201 | @code{file-name-nondirectory} are overridden within the @tramp{} |
2202 | package. | |
fb7933a3 KG |
2203 | |
2204 | Their replacements are reasonably simplistic in their approach. They | |
884b79ec KG |
2205 | dissect the filename, call the original handler on the localname and |
2206 | then rebuild the @tramp{} file name with the result. | |
fb7933a3 KG |
2207 | |
2208 | This allows the platform specific hacks in the original handlers to take | |
884b79ec | 2209 | effect while preserving the @tramp{} file name information. |
fb7933a3 KG |
2210 | |
2211 | ||
2212 | @node Issues | |
2213 | @chapter Debatable Issues and What Was Decided | |
2214 | ||
2215 | @itemize @bullet | |
2216 | @item The uuencode method does not always work. | |
2217 | ||
2218 | Due to the design of @tramp{}, the encoding and decoding programs need to | |
2219 | read from stdin and write to stdout. On some systems, @code{uudecode -o | |
2220 | -} will read stdin and write the decoded file to stdout, on other | |
2221 | systems @code{uudecode -p} does the same thing. But some systems have | |
2222 | uudecode implementations which cannot do this at all---it is not | |
2223 | possible to call these uudecode implementations with suitable parameters | |
2224 | so that they write to stdout. | |
2225 | ||
2226 | Of course, this could be circumvented: the @code{begin foo 644} line | |
2227 | could be rewritten to put in some temporary file name, then | |
2228 | @code{uudecode} could be called, then the temp file could be printed and | |
2229 | deleted. | |
2230 | ||
2231 | But I have decided that this is too fragile to reliably work, so on some | |
2232 | systems you'll have to do without the uuencode methods. | |
2233 | ||
2234 | @item @tramp{} does not work on XEmacs 20. | |
2235 | ||
2236 | This is because it requires the macro @code{with-timeout} which does not | |
2237 | appear to exist in XEmacs 20. I'm somewhat reluctant to add an | |
2238 | emulation macro to @tramp{}, but if somebody who uses XEmacs 20 steps | |
2239 | forward and wishes to implement and test it, please contact me or the | |
2240 | mailing list. | |
2241 | ||
f37fc5a7 KG |
2242 | @item The @tramp{} filename syntax differs between Emacs and XEmacs. |
2243 | ||
2244 | The Emacs maintainers wish to use a unified filename syntax for | |
2245 | Ange-FTP and @tramp{} so that users don't have to learn a new | |
2246 | syntax. It is sufficient to learn some extensions to the old syntax. | |
2247 | ||
2248 | For the XEmacs maintainers, the problems caused from using a unified | |
abc6be8d KG |
2249 | filename syntax are greater than the gains. The XEmacs package system |
2250 | uses EFS for downloading new packages. So, obviously, EFS has to be | |
2251 | installed from the start. If the filenames were unified, @tramp{} | |
f37fc5a7 KG |
2252 | would have to be installed from the start, too. |
2253 | ||
6b61353c KH |
2254 | @ifset xemacs |
2255 | @strong{Note:} If you'ld like to use a similar syntax like | |
2256 | @value{ftp-package-name}, you need the following settings in your init | |
2257 | file: | |
2258 | ||
2259 | @lisp | |
2260 | (setq tramp-unified-filenames t) | |
2261 | (require 'tramp) | |
2262 | @end lisp | |
2263 | ||
2264 | The autoload of the @value{emacs-name} @tramp{} package must be | |
2265 | disabled. This can be achieved by setting file permissions @code{000} | |
2266 | to the files @file{.../xemacs-packages/lisp/tramp/auto-autoloads.el*}. | |
2267 | ||
2268 | In case of unified filenames, all @value{emacs-name} download sites | |
2269 | are added to @code{tramp-default-method-alist} with default method | |
2270 | @code{ftp} @xref{Default Method}. These settings shouldn't be touched | |
2271 | for proper working of the @value{emacs-name} package system. | |
2272 | ||
2273 | The syntax for unified filenames is described in the @tramp{} manual | |
2274 | for @value{emacs-other-name}. | |
2275 | @end ifset | |
2276 | ||
fb7933a3 KG |
2277 | @end itemize |
2278 | ||
41bed43c KG |
2279 | @node Concept Index |
2280 | @comment node-name, next, previous, up | |
2281 | @unnumbered Concept Index | |
2282 | @printindex cp | |
2283 | @contents | |
fb7933a3 KG |
2284 | @c End of tramp.texi - the TRAMP User Manual |
2285 | @bye | |
2286 | ||
2287 | @c TODO | |
2288 | @c | |
2289 | @c * Say something about the .login and .profile files of the remote | |
2290 | @c shells. | |
2291 | @c * Explain how tramp.el works in principle: open a shell on a remote | |
2292 | @c host and then send commands to it. | |
83fa16cf KG |
2293 | @c * Mention that bookmarks are a cool feature to go along with Tramp. |
2294 | @c * Make terminology "inline" vs "out-of-band" consistent. | |
2295 | @c It seems that "external" is also used instead of "out-of-band". | |
fb7933a3 | 2296 | |
16674e4f KG |
2297 | @c * M. Albinus |
2298 | @c ** Use `filename' resp. `file name' consistently. | |
2299 | @c ** Use `host' resp. `machine' consistently. | |
2300 | @c ** Consistent small or capitalized words especially in menues. | |
6b61353c KH |
2301 | |
2302 | @ignore | |
2303 | arch-tag: f96dd66e-6dd3-4c92-8d77-9c56205ba808 | |
2304 | @end ignore |