Commit | Line | Data |
---|---|---|
fb7933a3 KG |
1 | \input texinfo @c -*-texinfo-*- |
2 | @c %**start of header | |
6344cbf1 | 3 | @setfilename ../info/tramp |
fb7933a3 KG |
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 | ||
fb7933a3 KG |
11 | |
12 | @c Entries for @command{install-info} to use | |
92eeeafc | 13 | @dircategory Emacs |
fb7933a3 KG |
14 | @direntry |
15 | * TRAMP: (tramp). Transparent Remote Access, Multiple Protocol | |
16 | Emacs remote file access via rsh and rcp. | |
17 | @end direntry | |
18 | ||
19 | @c Macro to make formatting of the tramp program name consistent. | |
20 | @macro tramp | |
21 | @sc{tramp} | |
22 | @end macro | |
23 | ||
24 | @c Copying permissions, et al | |
92eeeafc | 25 | @copying |
fb7933a3 KG |
26 | This file documents @tramp{}, a remote file editing package for Emacs and |
27 | XEmacs. | |
28 | ||
f37fc5a7 KG |
29 | Copyright @copyright{} 1999, 2000, 2001, 2002 Free Software |
30 | Foundation, Inc. | |
92eeeafc KG |
31 | |
32 | @quotation | |
33 | Permission is granted to copy, distribute and/or modify this document | |
34 | under the terms of the GNU Free Documentation License, Version 1.1 or | |
35 | any later version published by the Free Software Foundation; with no | |
36 | Invariant Sections, with the Front-Cover texts being ``A GNU | |
37 | Manual'', and with the Back-Cover Texts as in (a) below. A copy of the | |
38 | license is included in the section entitled ``GNU Free Documentation | |
39 | License'' in the Emacs manual. | |
40 | ||
41 | (a) The FSF's Back-Cover Text is: ``You have freedom to copy and modify | |
42 | this GNU Manual, like GNU software. Copies published by the Free | |
43 | Software Foundation raise funds for GNU development.'' | |
44 | ||
45 | This document is part of a collection distributed under the GNU Free | |
46 | Documentation License. If you want to distribute this document | |
47 | separately from the collection, you can do so by adding a copy of the | |
48 | license to the document, as described in section 6 of the license. | |
49 | @end quotation | |
50 | @end copying | |
51 | ||
fb7933a3 KG |
52 | |
53 | @tex | |
54 | ||
55 | @titlepage | |
56 | @title @tramp{} User Manual | |
fb7933a3 KG |
57 | |
58 | @author by Daniel Pittman | |
59 | @author based on documentation by Kai Gro@ss{}johann | |
60 | @page | |
61 | ||
fb7933a3 KG |
62 | @end titlepage |
63 | @page | |
64 | ||
65 | @end tex | |
66 | ||
67 | @ifnottex | |
92eeeafc | 68 | @node Top, Overview, (dir), (dir) |
fb7933a3 KG |
69 | @top @tramp{} User Manual |
70 | ||
71 | @tramp{} stands for `Transparent Remote (file) Access, Multiple | |
72 | Protocol'. This package provides remote file editing, similar to | |
92eeeafc | 73 | @cite{Ange-FTP} and @cite{EFS}. |
fb7933a3 | 74 | |
92eeeafc | 75 | The difference is that Ange-FTP uses FTP to transfer files between the |
fb7933a3 KG |
76 | local and the remote host, whereas @tramp{} uses a combination of |
77 | @command{rsh} and @command{rcp} or other work-alike programs, such as | |
78 | @command{ssh}/@command{scp}. | |
79 | ||
fb7933a3 KG |
80 | You can find the latest version of this document on the web at |
81 | @uref{http://www.freesoftware.fsf.org/tramp/}. | |
82 | ||
83 | @ifhtml | |
84 | This manual is also available as a @uref{tramp_ja.html, Japanese | |
85 | translation}. | |
86 | ||
87 | The latest release of @tramp{} is available for | |
88 | @uref{http://savannah.gnu.org/download/tramp/, | |
89 | download}, or you may see @ref{Obtaining @tramp{}} for more details, | |
90 | including the CVS server details. | |
91 | ||
92 | @tramp{} also has a @uref{https://savannah.gnu.org/projects/tramp/, | |
93 | Savannah Project Page}. | |
94 | @end ifhtml | |
95 | ||
96 | There is a mailing list for @tramp{}, available at | |
97 | @email{tramp-devel@@mail.freesoftware.fsf.org}, and archived at | |
98 | @uref{http://www.mail-archive.com/emacs-rcp@@ls6.cs.uni-dortmund.de/} as | |
99 | well as the usual Savannah archives. | |
100 | ||
101 | @end ifnottex | |
102 | ||
103 | @menu | |
fb7933a3 KG |
104 | * Overview:: What @tramp{} can and cannot do. |
105 | ||
106 | For the end user: | |
107 | * Obtaining @tramp{}:: How to obtain @tramp{}. | |
108 | * History:: History of @tramp{} | |
109 | * Installation:: Installing @tramp{} with your (X)Emacs. | |
110 | * Configuration:: Configuring @tramp{} for use. | |
111 | * Usage:: An overview of the operation of @tramp{}. | |
112 | * Bug Reports:: Reporting Bugs and Problems | |
113 | * Frequently Asked Questions:: Questions and answers from the mailing list. | |
114 | ||
115 | For the developer: | |
116 | * Version Control:: The inner workings of remote version control. | |
117 | * Files directories and paths:: How file names, directories and paths are mangled and managed. | |
118 | * Issues:: | |
119 | ||
120 | @detailmenu | |
121 | --- The Detailed Node Listing --- | |
122 | ||
123 | Configuring @tramp{} for use | |
124 | ||
125 | * Connection types:: Types of connections made to remote machines. | |
126 | * Inline methods:: Inline methods. | |
127 | * External transfer methods:: External transfer methods. | |
128 | * Multi-hop Methods:: Connecting to a remote host using multiple hops. | |
129 | * Default Method:: Selecting a default method. | |
130 | * Customizing Methods:: Using Non-Standard Methods. | |
131 | * Remote Programs:: How @tramp{} finds and uses programs on the remote machine. | |
132 | * Remote shell setup:: | |
133 | ||
134 | Using @tramp | |
135 | ||
136 | * Filename Syntax:: @tramp{} filename conventions. | |
137 | * Multi-hop filename syntax:: Multi-hop filename conventions | |
138 | * Dired:: Dired and filename completion. | |
139 | ||
140 | The inner workings of remote version control | |
141 | ||
142 | * Version Controlled Files:: Determining if a file is under version control. | |
143 | * Remote Commands:: Executing the version control commands on the remote machine. | |
144 | * Changed workfiles:: Detecting if the working file has changed. | |
145 | * Checking out files:: Bringing the workfile out of the repository. | |
146 | * Miscellaneous Version Control:: Things related to Version Control that don't fit elsewhere | |
147 | ||
148 | Things related to Version Control that don't fit elsewhere | |
149 | ||
150 | * Remote File Ownership:: How VC determines who owns a workfile. | |
151 | * Back-end Versions:: How VC determines what release your RCS is. | |
152 | ||
153 | How file names, directories and paths are mangled and managed. | |
154 | ||
155 | * Path deconstruction:: Breaking a path into its components. | |
156 | ||
157 | @end detailmenu | |
158 | @end menu | |
159 | ||
fb7933a3 KG |
160 | |
161 | @node Overview | |
162 | @chapter An overview of @tramp | |
92eeeafc | 163 | @cindex overview |
fb7933a3 | 164 | |
92eeeafc KG |
165 | After the installation of @tramp{} into your Emacs, you will be able |
166 | to access files on remote machines as though they were local. Access | |
167 | to the remote file system for editing files, version control, and | |
fb7933a3 KG |
168 | @command{dired} are transparently enabled. |
169 | ||
170 | Your access to the remote machine can be with the @command{rsh}, | |
171 | @command{rlogin}, @command{telnet} programs or with any similar | |
92eeeafc | 172 | connection method. This connection must pass ASCII successfully to be |
fb7933a3 KG |
173 | usable but need not be 8-bit clean. |
174 | ||
175 | The package provides support for @command{ssh} connections out of the | |
92eeeafc KG |
176 | box, one of the more common uses of the package. This allows |
177 | relatively secure access to machines, especially if @command{ftp} | |
178 | access is disabled. | |
fb7933a3 | 179 | |
92eeeafc KG |
180 | The majority of activity carried out by @tramp{} requires only that |
181 | the remote login is possible and is carried out at the terminal. In | |
182 | order to access remote files @tramp{} needs to transfer their content | |
183 | to the local machine temporarily. | |
fb7933a3 | 184 | |
92eeeafc KG |
185 | @tramp{} can transfer files between the machines in a variety of ways. |
186 | The details are easy to select, depending on your needs and the | |
187 | machines in question. | |
fb7933a3 | 188 | |
92eeeafc KG |
189 | The fastest transfer methods (for large files) rely on a remote file |
190 | transfer package such as @command{rcp}, @command{scp} or | |
191 | @command{rsync}. The use of these methods is only possible if the | |
192 | file copy command does not ask for a password for the remote machine. | |
fb7933a3 KG |
193 | |
194 | If the remote copy methods are not suitable for you, @tramp{} also | |
92eeeafc KG |
195 | supports the use of encoded transfers directly through the shell. |
196 | This requires that the @command{mimencode} or @command{uuencode} tools | |
197 | are available on the remote machine. These methods are generally | |
198 | faster for small files. | |
fb7933a3 | 199 | |
92eeeafc KG |
200 | Within these limitations, @tramp{} is quite powerful. It is worth |
201 | noting that, as of the time of writing, it is far from a polished | |
202 | end-user product. For a while yet you should expect to run into rough | |
203 | edges and problems with the code now and then. | |
fb7933a3 KG |
204 | |
205 | It is finished enough that the developers use it for day to day work but | |
206 | the installation and setup can be a little difficult to master, as can | |
207 | the terminology. | |
208 | ||
209 | @tramp{} is still under active development and any problems you encounter, | |
210 | trivial or major, should be reported to the @tramp{} developers. | |
211 | @xref{Bug Reports}. | |
212 | ||
213 | ||
214 | @subsubheading Behind the scenes | |
92eeeafc | 215 | @cindex behind the scenes |
e28e4d20 KG |
216 | @cindex details of operation |
217 | @cindex how it works | |
fb7933a3 KG |
218 | |
219 | This section tries to explain what goes on behind the scenes when you | |
220 | access a remote file through @tramp{}. | |
221 | ||
222 | Suppose you type @kbd{C-x C-f} and enter part of an @tramp{} file name, | |
223 | then hit @kbd{@key{TAB}} for completion. Suppose further that this is | |
224 | the first time that @tramp{} is invoked for the host in question. Here's | |
225 | what happens: | |
226 | ||
227 | @itemize | |
228 | @item | |
92eeeafc KG |
229 | @tramp{} discovers that it needs a connection to the host. So it |
230 | invokes @samp{telnet @var{host}} or @samp{rsh @var{host} -l | |
231 | @var{user}} or a similar tool to connect to the remote host. | |
232 | Communication with this process happens through an Emacs buffer, that | |
233 | is, the output from the remote end goes into a buffer. | |
fb7933a3 KG |
234 | |
235 | @item | |
236 | The remote host may prompt for a login name (for @command{telnet}). The | |
237 | login name is given in the file name, so @tramp{} sends the login name and | |
238 | a newline. | |
239 | ||
240 | @item | |
241 | The remote host may prompt for a password or pass phrase (for | |
242 | @command{rsh} or for @command{telnet} after sending the login name). | |
243 | @tramp{} displays the prompt in the minibuffer, asking you for the | |
244 | password or pass phrase. | |
245 | ||
246 | You enter the password or pass phrase. @tramp{} sends it to the remote | |
247 | host, followed by a newline. | |
248 | ||
249 | @item | |
250 | @tramp{} now waits for the shell prompt or for a message that the login | |
251 | failed. | |
252 | ||
253 | If @tramp{} sees neither of them after a certain period of time (a minute, | |
254 | say), then it issues an error message saying that it couldn't find the | |
255 | remote shell prompt and shows you what the remote host has sent. | |
256 | ||
257 | If @tramp{} sees a `login failed' message, it tells you so, aborts the | |
258 | login attempt and allows you to try again. | |
259 | ||
260 | @item | |
261 | Suppose that the login was successful and @tramp{} sees the shell prompt | |
262 | from the remote host. Now @tramp{} invokes @command{/bin/sh} because | |
263 | Bourne shells and C shells have different command | |
264 | syntaxes.@footnote{Invoking @command{/bin/sh} will fail if your login | |
92eeeafc | 265 | shell doesn't recognize @samp{exec /bin/sh} as a valid command. |
fb7933a3 KG |
266 | Maybe you use the Scheme shell @command{scsh}@dots{}} |
267 | ||
268 | After the Bourne shell has come up, @tramp{} sends a few commands to | |
269 | ensure a good working environment. It turns off echoing, it sets the | |
270 | shell prompt, and a few other things. | |
271 | ||
272 | @item | |
273 | Now the remote shell is up and it good working order. Remember, what | |
274 | was supposed to happen is that @tramp{} tries to find out what files exist | |
275 | on the remote host so that it can do filename completion. | |
276 | ||
277 | So, @tramp{} basically issues @command{cd} and @command{ls} commands and | |
278 | also sometimes @command{echo} with globbing. Another command that is | |
279 | often used is @command{test} to find out whether a file is writable or a | |
280 | directory or the like. The output of each command is parsed for the | |
281 | necessary operation. | |
282 | ||
283 | @item | |
284 | Suppose you are finished with filename completion, have entered @kbd{C-x | |
285 | C-f}, a full file name and hit @kbd{@key{RET}}. Now comes the time to | |
286 | transfer the file contents from the remote host to the local host so | |
287 | that you can edit them. | |
288 | ||
289 | See above for an explanation of how @tramp{} transfers the file contents. | |
290 | ||
92eeeafc | 291 | For inline transfers, @tramp{} issues a command like @samp{mimencode -b |
fb7933a3 KG |
292 | /path/to/remote/file}, waits until the output has accumulated in the |
293 | buffer that's used for communication, then decodes that output to | |
294 | produce the file contents. | |
295 | ||
92eeeafc | 296 | For out-of-band transfers, @tramp{} issues a command like @samp{rcp |
fb7933a3 KG |
297 | user@@host:/path/to/remote/file /tmp/tramp.4711} and then reads the local |
298 | temporary file @file{/tmp/tramp.4711} into a buffer and deletes the | |
299 | temporary file. | |
300 | ||
301 | @item | |
302 | You now edit the buffer contents, blithely unaware of what has happened | |
303 | behind the scenes. (Unless you have read this section, that is.) When | |
304 | you are finished, you type @kbd{C-x C-s} to save the buffer. | |
305 | ||
306 | @item | |
307 | Again, @tramp{} transfers the file contents to the remote host either | |
308 | inline or out-of-band. This is the reverse of what happens when reading | |
309 | the file. | |
310 | ||
311 | @end itemize | |
312 | ||
313 | I hope this has provided you with a basic overview of what happens | |
314 | behind the scenes when you open a file with @tramp{}. | |
315 | ||
316 | ||
317 | @c For the end user | |
318 | @node Obtaining @tramp{} | |
319 | @chapter Obtaining @tramp{}. | |
92eeeafc | 320 | @cindex obtaining Tramp |
fb7933a3 KG |
321 | |
322 | @tramp{} is freely available on the Internet and the latest release may be | |
323 | downloaded from | |
324 | @uref{ftp://ls6-ftp.cs.uni-dortmund.de/pub/src/emacs/tramp.tar.gz}. This | |
325 | release includes the full documentation and code for @tramp{}, suitable | |
92eeeafc KG |
326 | for installation. But Emacs (21.4 or later) includes @tramp{} |
327 | already, and there is a @tramp{} package for XEmacs, as well. So | |
328 | maybe it is easier to just use those. But if you want the bleeding | |
329 | edge, read on@dots{...} | |
fb7933a3 | 330 | |
92eeeafc | 331 | For the especially brave, @tramp{} is available from CVS. The CVS version |
fb7933a3 KG |
332 | is the latest version of the code and may contain incomplete features or |
333 | new issues. Use these versions at your own risk. | |
334 | ||
335 | Instructions for obtaining the latest development version of @tramp{} | |
336 | from CVS can be found by going to the Savannah project page at | |
337 | @uref{http://savannah.gnu.org/projects/tramp/} and then clicking on the | |
338 | CVS link in the navigation bar at the top. Or follow the example | |
339 | session below: | |
340 | ||
341 | @example | |
342 | ] @strong{cd ~/lisp} | |
343 | ] @strong{cvs -d:pserver:anoncvs@@subversions.gnu.org:/cvsroot/tramp login} | |
344 | ||
345 | (Logging in to anoncvs@@subversions.gnu.org) | |
346 | CVS password: @strong{(just hit RET here)} | |
347 | @dots{} | |
348 | ||
349 | ] @strong{cvs -z3 -d:pserver:anoncvs@@subversions.gnu.org:/cvsroot/tramp co tramp} | |
350 | @end example | |
351 | ||
352 | You should now have a directory @file{~/lisp/tramp} containing the latest | |
353 | version of @tramp{}. You can fetch the latest updates from the repository | |
354 | by issuing the command: | |
355 | ||
356 | @example | |
357 | ] @strong{cd ~/lisp/tramp} | |
358 | ] @strong{cvs update -d} | |
359 | @end example | |
360 | ||
361 | ||
362 | @node History | |
363 | @chapter History of @tramp{} | |
92eeeafc KG |
364 | @cindex history |
365 | @cindex development history | |
fb7933a3 KG |
366 | |
367 | Development was started end of November 1998. The package was called | |
92eeeafc KG |
368 | @file{rssh.el}, back then. It only provided one method to access a |
369 | file, using @command{ssh} to log in to a remote host and using | |
370 | @command{scp} to transfer the file contents. After a while, the name | |
371 | was changed to @file{rcp.el}, and now it's @tramp{}. Along the way, | |
372 | many more methods for getting a remote shell and for transferring the | |
373 | file contents were added. Support for VC was added. | |
fb7933a3 | 374 | |
92eeeafc KG |
375 | The most recent addition of major features were the multi-hop methods |
376 | added in April 2000 and the unification of @tramp{} and Ange-FTP | |
377 | filenames in July 2002. | |
fb7933a3 KG |
378 | |
379 | ||
380 | @node Installation | |
381 | @chapter Installing @tramp{} into Emacs or XEmacs | |
92eeeafc | 382 | @cindex installation |
fb7933a3 | 383 | |
92eeeafc KG |
384 | If you use the version that comes with your Emacs or the XEmacs |
385 | package, the following information is not necessary. Installing | |
386 | @tramp{} into your Emacs or XEmacs is a relatively easy process, at | |
387 | least compared to rebuilding your machine from scratch. ;) | |
fb7933a3 KG |
388 | |
389 | Seriously though, the installation should be a fairly simple matter. | |
390 | ||
391 | The easiest way to proceed is as follows: | |
392 | ||
393 | @itemize | |
394 | @item | |
395 | Choose a directory, say @file{~/emacs/}. Change into that directory and | |
396 | unpack the tarball. This will give you a directory | |
397 | @file{~/emacs/tramp/} which contains subdirectories @file{lisp} for the | |
398 | Lisp code and @file{texi} for the documentation. | |
399 | ||
400 | @item | |
401 | Optionally byte-compile all files in the Lisp directory, | |
402 | @file{~/emacs/tramp/lisp/}, by issuing a command like the following from | |
403 | the top level directory @file{~/emacs/tramp/}: | |
404 | @example | |
405 | make EMACS=emacs all # for Emacs users | |
406 | make EMACS=xemacs all # for XEmacs users | |
407 | @end example | |
408 | ||
409 | @item | |
410 | NOTE: | |
411 | @example | |
412 | If you run into problems running the example @command{make} | |
413 | commands, don't dispare. You can still byte compile the | |
414 | @file{*.el} files by opening emacs in @command{dired} | |
415 | (@command{C-x d}) mode, at @file{~/tramp/lisp}. Mark the lisp | |
92eeeafc | 416 | files with @kbd{m}, then press @kbd{B} to byte compile |
fb7933a3 KG |
417 | your selections. |
418 | ||
419 | Something similar can be done to create the info manual. | |
420 | Just cd to @file{~/emacs/tramp/texi} and load the @file{tramp.texi} | |
92eeeafc | 421 | file in emacs. Then press @kbd{M-x makeinfo-buffer <RET>} |
fb7933a3 KG |
422 | to generate @file{tramp.info}. |
423 | @end example | |
424 | ||
425 | @item | |
426 | Tell Emacs about the new Lisp directory and the @tramp{} package | |
427 | with the following lines in @file{~/.emacs}: | |
428 | @lisp | |
429 | (add-to-list 'load-path "~/emacs/tramp/lisp/") | |
430 | (require 'tramp) | |
431 | @end lisp | |
432 | ||
433 | @item | |
434 | To be able to read the Info documentation, create a file | |
435 | @file{~/emacs/tramp/texi/dir} using for example the | |
436 | @command{install-info} command, and add the directory to the search | |
437 | path for Info. | |
438 | ||
439 | @item | |
440 | NOTE: | |
441 | @example | |
442 | On systems using `gnu' @command{install-info}, the | |
443 | @command{install-info} syntax is very direct and simple. One can | |
444 | cd to @file{~/emacs/tramp/texi} and type: | |
92eeeafc | 445 | @kbd{install-info tramp.info dir} |
fb7933a3 KG |
446 | and a @file{dir} file will be created with the @tramp{} |
447 | entry. The info reader will know how to interpret it, but must | |
448 | be told where to find it (see below). If you want anything fancier | |
92eeeafc | 449 | you'll need to look through @kbd{man install-info}. |
fb7933a3 KG |
450 | |
451 | Debian gnu/linux doesn't default to `gnu' @command{install-info} and | |
452 | uses its own version. This version does not create a @file{dir} file | |
453 | for you from scratch. You must provide a skeleton dir file it | |
454 | recognizes. One can be found in a default install at | |
455 | @file{/usr/info/dir}. Copy the top of this file down to the first | |
456 | occurrence of `* Menu' including that line plus one more blank line, | |
457 | to your working directory @file{texi/dir}, or use the sample provided | |
458 | in the @file{texi} directroy of this distribution. See | |
459 | @file{texi/dir_sample} | |
460 | ||
461 | Once a @file{dir} file is in place, this command will make the entry. | |
462 | install-info --infodir=. tramp.info | |
463 | If you want it in a specific category | |
92eeeafc | 464 | (see @kbd{man install-info} for further details) |
fb7933a3 KG |
465 | @end example |
466 | ||
467 | If the environment variable @env{INFOPATH} is set, add the directory | |
468 | @file{~/emacs/tramp/texi/} to it. Else, add the directory to | |
469 | @code{Info-default-directory-list}, as follows: | |
470 | @lisp | |
471 | (add-to-list 'Info-default-directory-list "~/emacs/tramp/texi/") | |
472 | @end lisp | |
473 | XEmacs 21 users should use @code{Info-directory-list} rather than | |
474 | @code{Info-default-directory-list}. | |
475 | ||
476 | @end itemize | |
477 | ||
478 | ||
92eeeafc | 479 | For XEmacs users, the package @file{fsf-compat} must be installed. |
fb7933a3 KG |
480 | For details on package installation, see @ref{Packages, , ,xemacs}. |
481 | @ifhtml | |
482 | (If the previous link doesn't work, try the XEmacs documentation at | |
483 | @uref{http://www.xemacs.org/Documentation/packageGuide.html,the XEmacs | |
484 | site}.) | |
485 | @end ifhtml | |
486 | ||
487 | @node Configuration | |
488 | @chapter Configuring @tramp{} for use | |
92eeeafc | 489 | @cindex configuration |
fb7933a3 | 490 | |
92eeeafc | 491 | @cindex default configuration |
fb7933a3 | 492 | @tramp{} is (normally) fully functional when it is initially |
92eeeafc KG |
493 | installed. It is initially configured to use the @command{sh} program |
494 | to connect to the remote host and to use base-64 encoding (on the | |
495 | remote host, via @command{mimencode}, and on the local host via the | |
496 | built-in support for base-64 encoding in Emacs). | |
fb7933a3 KG |
497 | |
498 | On some hosts, there are problems with opening a connection. These are | |
499 | related to the behavior of the remote shell. See @xref{Remote shell | |
500 | setup}, for details on this. | |
501 | ||
92eeeafc KG |
502 | If you do not wish to use these commands to connect to the remote |
503 | host, you should change the default connection and transfer method | |
504 | that @tramp uses. There are several different methods that @tramp{} | |
505 | can use to connect to remote machines and transfer files | |
506 | (@pxref{Connection types}). | |
fb7933a3 KG |
507 | |
508 | ||
509 | @menu | |
510 | * Connection types:: Types of connections made to remote machines. | |
511 | * Inline methods:: Inline methods. | |
512 | * External transfer methods:: External transfer methods. | |
513 | * Multi-hop Methods:: Connecting to a remote host using multiple hops. | |
514 | * Default Method:: Selecting a default method. | |
515 | * Customizing Methods:: Using Non-Standard Methods. | |
516 | * Remote Programs:: How @tramp{} finds and uses programs on the remote machine. | |
517 | * Remote shell setup:: Remote shell setup hints. | |
518 | * Windows setup hints:: Issues with Cygwin ssh. | |
519 | @end menu | |
520 | ||
521 | ||
522 | @node Connection types | |
523 | @section Types of connections made to remote machines. | |
92eeeafc | 524 | @cindex connection types, overview |
fb7933a3 KG |
525 | |
526 | There are two basic types of transfer methods, each with its own | |
92eeeafc | 527 | advantages and limitations. Both types of connection make use of a |
fb7933a3 KG |
528 | remote shell access program such as @command{rsh}, @command{ssh} or |
529 | @command{telnet} to connect to the remote machine. | |
530 | ||
531 | This connection is used to perform many of the operations that @tramp | |
532 | requires to make the remote file system transparently accessible from | |
533 | the local machine. It is only when visiting files that the methods | |
534 | differ. | |
535 | ||
92eeeafc KG |
536 | @cindex inline methods |
537 | @cindex external transfer methods | |
538 | @cindex external methods | |
539 | @cindex out-of-band methods | |
540 | @cindex methods, inline | |
541 | @cindex methods, external transfer | |
542 | @cindex methods, out-of-band | |
543 | Loading or saving a remote file requires that the content of the file | |
544 | be transfered between the two machines. The content of the file can be | |
545 | transfered over the same connection used to log in to the remote | |
546 | machine or the file can be transfered through another connection using | |
547 | a remote copy program such as @command{rcp}, @command{scp} or | |
548 | @command{rsync}. The former are called @dfn{inline methods}, the | |
549 | latter are called @dfn{out-of-band methods} or @dfn{external transfer | |
550 | methods} (@dfn{external methods} for short). | |
fb7933a3 KG |
551 | |
552 | The performance of the external transfer methods is generally better | |
92eeeafc KG |
553 | than that of the inline methods, at least for large files. This is |
554 | caused by the need to encode and decode the data when transferring | |
555 | inline. | |
fb7933a3 KG |
556 | |
557 | The one exception to this rule are the @command{scp} based transfer | |
558 | methods. While these methods do see better performance when actually | |
559 | transferring files, the overhead of the cryptographic negotiation at | |
560 | startup may drown out the improvement in file transfer times. | |
561 | ||
562 | External transfer methods do require that the remote copy command is not | |
563 | interactive --- that is, the command does not prompt you for a password. | |
564 | If you cannot perform remote copies without a password, you will need to | |
565 | use an inline transfer method to work with @tramp{}. | |
566 | ||
92eeeafc KG |
567 | @cindex multi-hop methods |
568 | @cindex methods, multi-hop | |
fb7933a3 KG |
569 | A variant of the inline methods are the @dfn{multi-hop methods}. |
570 | These methods allow you to connect a remote host using a number `hops', | |
571 | each of which connects to a different host. This is useful if you are | |
572 | in a secured network where you need to go through a bastion host to | |
573 | connect to the outside world. | |
574 | ||
575 | ||
576 | @node Inline methods | |
577 | @section Inline methods | |
92eeeafc KG |
578 | @cindex inline methods |
579 | @cindex methods, inline | |
fb7933a3 KG |
580 | |
581 | The inline methods in @tramp{} are quite powerful and can work in | |
582 | situations where you cannot use an external transfer program to connect. | |
583 | Inline methods are the only methods that work when connecting to the | |
584 | remote machine via telnet. (There are also strange inline methods which | |
585 | allow you to transfer files between @emph{user identities} rather than | |
586 | hosts, see below.) | |
587 | ||
588 | These methods depend on the existence of a suitable encoding and | |
92eeeafc | 589 | decoding command on remote machine. Locally, @tramp{} may be able to use |
fb7933a3 KG |
590 | features of Emacs to decode and encode the files or it may require |
591 | access to external commands to perform that task. | |
592 | ||
92eeeafc KG |
593 | @cindex uuencode |
594 | @tramp{} supports the use of @command{uuencode} to transfer files. | |
595 | This is @emph{not} recommended. The @command{uuencode} and | |
596 | @command{uudecode} commands are not well standardized and may not | |
597 | function correctly or at all on some machines, notably AIX and IRIX. | |
598 | These systems do not work with @command{uuencode} at all. (But do see | |
599 | the note about AIX in the documentation for @var{tramp-methods}.) | |
fb7933a3 | 600 | |
92eeeafc KG |
601 | @cindex mimencode |
602 | @cindex base-64 encoding | |
fb7933a3 KG |
603 | In summary, if possible use the @command{mimencode} methods to transfer |
604 | the data base64 encoded. This has the advantage of using a built-in | |
605 | command in every modern Emacs, improving performance. | |
606 | ||
92eeeafc | 607 | @table @asis |
fb7933a3 | 608 | @item @option{rm} --- @command{rsh} with @command{mimencode} |
92eeeafc KG |
609 | @cindex method rm |
610 | @cindex rm method | |
e28e4d20 | 611 | @cindex method using rsh (rm) |
fb7933a3 KG |
612 | |
613 | Connect to the remote host with @command{rsh} and use base64 encoding to | |
614 | transfer files between the machines. | |
615 | ||
616 | This requires the @command{mimencode} command that is part of the | |
617 | @command{metamail} packages. This may not be installed on all remote | |
618 | machines. | |
619 | ||
620 | ||
621 | @item @option{sm} --- @command{ssh} with @command{mimencode} | |
92eeeafc KG |
622 | @cindex method sm |
623 | @cindex sm method | |
e28e4d20 KG |
624 | @cindex method using ssh (sm) |
625 | @cindex ssh (with sm method) | |
626 | @cindex mimencode (with sm method) | |
627 | @cindex base-64 encoding (with sm method) | |
fb7933a3 KG |
628 | |
629 | Connect to the remote host with @command{ssh} and use base64 encoding to | |
630 | transfer files between the machines. | |
631 | ||
632 | This is identical to the previous option except that the @command{ssh} | |
633 | package is used, making the connection more secure. | |
634 | ||
635 | There are also two variants, @option{sm1} and @option{sm2} that use the | |
636 | @command{ssh1} and @command{ssh2} commands explicitly. If you don't know | |
637 | what these are, you do not need these options. | |
638 | ||
8e3a1104 KG |
639 | All the methods based on @command{ssh} have an additional kludgy |
640 | feature: you can specify a host name which looks like @file{host#42} | |
641 | (the real host name, then a hash sign, then a port number). This | |
642 | means to connect to the given host but to also pass @code{-p 42} as | |
643 | arguments to the @command{ssh} command. | |
644 | ||
fb7933a3 KG |
645 | |
646 | @item @option{tm} --- @command{telnet} with @command{mimencode} | |
92eeeafc KG |
647 | @cindex method tm |
648 | @cindex tm method | |
e28e4d20 KG |
649 | @cindex method using telnet (tm) |
650 | @cindex telnet (with tm method) | |
651 | @cindex mimencode (with tm method) | |
652 | @cindex base-64 encoding (with tm method) | |
fb7933a3 KG |
653 | |
654 | Connect to the remote host with @command{telnet} and use base64 encoding | |
655 | to transfer files between the machines. | |
656 | ||
657 | This requires the @command{mimencode} command that is part of the | |
658 | @command{metamail} packages. | |
659 | ||
660 | ||
661 | @item @option{ru} --- @command{rsh} with @command{uuencode} | |
92eeeafc KG |
662 | @cindex method ru |
663 | @cindex ru method | |
664 | @cindex method using rsh | |
e28e4d20 KG |
665 | @cindex rsh (with ru method) |
666 | @cindex uuencode (with ru method) | |
fb7933a3 KG |
667 | |
668 | Connect to the remote host with @command{rsh} and use the | |
669 | @command{uuencode} and @command{uudecode} commands to transfer files | |
670 | between the machines. | |
671 | ||
672 | ||
673 | @item @option{su} --- @command{ssh} with @command{uuencode} | |
92eeeafc KG |
674 | @cindex method su |
675 | @cindex su method | |
e28e4d20 KG |
676 | @cindex method using ssh (su) |
677 | @cindex ssh (with su method) | |
678 | @cindex uuencode (with su method) | |
fb7933a3 KG |
679 | |
680 | Connect to the remote host with @command{ssh} and use the | |
681 | @command{uuencode} and @command{uudecode} commands to transfer files | |
682 | between the machines. | |
683 | ||
8e3a1104 KG |
684 | As with the @command{ssh} and base64 option (@option{sm}) above, this |
685 | provides the @option{su1} and @option{su2} methods to explicitly | |
686 | select an ssh version. | |
fb7933a3 KG |
687 | |
688 | Note that this method does not invoke the @command{su} program, see | |
689 | below for methods which use that. | |
690 | ||
92eeeafc | 691 | This supports the @samp{-p} kludge. |
8e3a1104 | 692 | |
fb7933a3 KG |
693 | |
694 | @item @option{tu} --- @command{telnet} with @command{uuencode} | |
92eeeafc KG |
695 | @cindex tu method |
696 | @cindex method tu | |
e28e4d20 KG |
697 | @cindex method using telnet (tu) |
698 | @cindex telnet (with tu method) | |
699 | @cindex uuencode (with tu method) | |
fb7933a3 KG |
700 | |
701 | Connect to the remote host with @command{telnet} and use the | |
702 | @command{uuencode} and @command{uudecode} commands to transfer files | |
703 | between the machines. | |
704 | ||
705 | ||
706 | @item @option{sum} --- @command{su} with @command{mimencode} | |
92eeeafc KG |
707 | @cindex method sum |
708 | @cindex sum method | |
e28e4d20 KG |
709 | @cindex method using su (sum) |
710 | @cindex su (with sum method) | |
711 | @cindex mimencode (with sum method) | |
712 | @cindex base-64 encoding (with sum method) | |
fb7933a3 KG |
713 | |
714 | This method does not connect to a remote host at all, rather it uses the | |
715 | @command{su} program to allow you to edit files as another user. Uses | |
716 | base64 encoding to transfer the file contents. | |
717 | ||
718 | ||
719 | @item @option{suu} --- @command{su} with @command{uuencode} | |
92eeeafc KG |
720 | @cindex method suu |
721 | @cindex suu method | |
e28e4d20 KG |
722 | @cindex method using su (suu) |
723 | @cindex su (with suu method) | |
724 | @cindex uuencode (with suu method) | |
fb7933a3 KG |
725 | |
726 | Like @option{sum}, this uses the @command{su} program to allow you to | |
727 | edit files on the local host as another user. Uses @command{uuencode} | |
728 | and @command{uudecode} to transfer the file contents. | |
729 | ||
730 | ||
731 | @item @option{sudm} --- @command{sudo} with @command{mimencode} | |
92eeeafc KG |
732 | @cindex method sudm |
733 | @cindex sudm method | |
e28e4d20 KG |
734 | @cindex method using sudo (sudm) |
735 | @cindex sudo (with sudm method) | |
736 | @cindex mimencode (with sudm method) | |
737 | @cindex base-64 encoding (with sudm method) | |
fb7933a3 KG |
738 | |
739 | This is similar to the @option{sum} method, but it uses @command{sudo} | |
740 | rather than @command{su} to become a different user. | |
741 | ||
742 | Note that @command{sudo} must be configured to allow you to start a | |
743 | shell as the user. It would be nice if it was sufficient if | |
744 | @command{ls} and @command{mimencode} were allowed, but that is not easy | |
745 | to implement, so I haven't got around to it, yet. | |
746 | ||
747 | ||
748 | @item @option{sudu} --- @command{sudo} with @command{uuencode} | |
92eeeafc KG |
749 | @cindex method sudu |
750 | @cindex sudu method | |
e28e4d20 KG |
751 | @cindex method using sudo (sudu) |
752 | @cindex sudo (with sudu method) | |
753 | @cindex uuencode (with sudu method) | |
fb7933a3 KG |
754 | |
755 | This is similar to the @option{suu} method, but it uses @command{sudo} | |
756 | rather than @command{su} to become a different user. | |
757 | ||
758 | ||
759 | @item @option{smx} --- @command{ssh} with @command{mimencode} | |
92eeeafc KG |
760 | @cindex method smx |
761 | @cindex smx method | |
e28e4d20 KG |
762 | @cindex method using ssh (smx) |
763 | @cindex ssh (with smx method) | |
764 | @cindex mimencode (with smx method) | |
765 | @cindex base-64 encoding (with smx method) | |
766 | @cindex Cygwin (with smx method) | |
fb7933a3 KG |
767 | |
768 | As you expect, this is similar to @option{sm}, only a little | |
769 | different. Whereas @option{sm} opens a normal interactive shell on | |
92eeeafc KG |
770 | the remote host, this option uses @samp{ssh -t -t @var{host} -l |
771 | @var{user} /bin/sh} tp open a connection. This is useful for users | |
772 | where the normal login shell is set up to ask them a number of | |
773 | questions when logging in. This procedure avoids these questions, and | |
774 | just gives @tramp{} a more-or-less `standard' login shell to work | |
775 | with. | |
fb7933a3 | 776 | |
83fa16cf KG |
777 | Note that this procedure does not eliminate questions asked by |
778 | @command{ssh} itself. For example, @command{ssh} might ask ``Are you | |
779 | sure you want to continue connecting?'' if the host key of the remote | |
780 | host is not known. Tramp does not know how to deal with such a | |
781 | question (yet), therefore you will need to make sure that you can log | |
782 | in without such questions. | |
783 | ||
fb7933a3 KG |
784 | This is also useful for Windows users where @command{ssh}, when |
785 | invoked from an Emacs buffer, tells them that it is not allocating a | |
786 | pseudo tty. When this happens, the login shell is wont to not print | |
92eeeafc KG |
787 | any shell prompt, which confuses @tramp{} mightily. For reasons |
788 | unknown, some Windows ports for @command{ssh} (maybe the Cygwin one) | |
789 | require the doubled @samp{-t} option. | |
fb7933a3 | 790 | |
92eeeafc | 791 | This supports the @samp{-p} kludge. |
8e3a1104 | 792 | |
fb7933a3 KG |
793 | |
794 | @item @option{km} --- @command{krlogin} with @command{mimencode} | |
92eeeafc KG |
795 | @cindex method km |
796 | @cindex km method | |
e28e4d20 KG |
797 | @cindex krlogin (with km method) |
798 | @cindex Kerberos (with km method) | |
799 | @cindex mimencode (with km method) | |
800 | @cindex base-64 encoding (with km method) | |
fb7933a3 KG |
801 | |
802 | This method is also similar to @option{sm}. It only uses the | |
803 | @command{krlogin -x} command to log in to the remote host. | |
804 | ||
805 | ||
806 | @item @option{plinku} --- @command{plink} with @command{uuencode} | |
92eeeafc KG |
807 | @cindex method plinku |
808 | @cindex plinku method | |
e28e4d20 KG |
809 | @cindex method using plink (plinku) |
810 | @cindex plink (with plinku method) | |
811 | @cindex uuencode (with plinku method) | |
fb7933a3 KG |
812 | |
813 | This method is mostly interesting for Windows users using the PuTTY | |
92eeeafc | 814 | implementation of SSH. It uses @samp{plink -ssh} to log in to the |
fb7933a3 KG |
815 | remote host. |
816 | ||
817 | CCC: Do we have to connect to the remote host once from the command | |
818 | line to accept the SSH key? Maybe this can be made automatic? | |
819 | ||
92eeeafc | 820 | CCC: Does @command{plink} support the @samp{-p} option? Tramp |
8e3a1104 KG |
821 | will support that, anyway. |
822 | ||
fb7933a3 | 823 | @item @option{plinkm} --- @command{plink} with @command{mimencode} |
92eeeafc KG |
824 | @cindex method plinkm |
825 | @cindex plinkm method | |
e28e4d20 KG |
826 | @cindex method using plink (plinkm) |
827 | @cindex plink (with plinkm method) | |
828 | @cindex mimencode (with plinkm method) | |
829 | @cindex base-64 encoding (with plinkm method) | |
fb7933a3 KG |
830 | |
831 | Like @option{plinku}, but uses base64 encoding instead of uu encoding. | |
832 | ||
92eeeafc | 833 | @end table |
fb7933a3 KG |
834 | |
835 | ||
836 | ||
837 | @node External transfer methods | |
838 | @section External transfer methods | |
92eeeafc KG |
839 | @cindex methods, external transfer |
840 | @cindex methods, out-of-band | |
841 | @cindex external transfer methods | |
842 | @cindex out-of-band methods | |
fb7933a3 KG |
843 | |
844 | The external transfer methods operate through multiple channels, using | |
845 | the remote shell connection for many actions while delegating file | |
846 | transfers to an external transfer utility. | |
847 | ||
848 | This saves the overhead of encoding and decoding that multiplexing the | |
849 | transfer through the one connection has with the inline methods. | |
850 | ||
851 | If you want to use an external transfer method you @emph{must} be able | |
852 | to execute the transfer utility to copy files to and from the remote | |
853 | machine without any interaction. | |
854 | ||
92eeeafc | 855 | @cindex ssh-agent |
fb7933a3 KG |
856 | This means that you will need to use @command{ssh-agent} if you use the |
857 | @command{scp} program for transfers, or maybe your version of | |
858 | @command{scp} accepts a password on the command line.@footnote{PuTTY's | |
859 | @command{pscp} allows you to specify the password on the command line.} | |
860 | If you use @command{rsync} via @command{ssh} then the same rule must | |
861 | apply to that connection. | |
862 | ||
863 | If you cannot get @command{scp} to run without asking for a password but | |
864 | would still like to use @command{ssh} to secure your connection, have a | |
865 | look at the @command{ssh} based inline methods. | |
866 | ||
867 | ||
92eeeafc | 868 | @table @asis |
fb7933a3 | 869 | @item @option{rcp} --- @command{rsh} and @command{rcp} |
92eeeafc KG |
870 | @cindex method rcp |
871 | @cindex rcp method | |
e28e4d20 KG |
872 | @cindex rcp (with rcp method) |
873 | @cindex rsh (with rcp method) | |
fb7933a3 KG |
874 | |
875 | This method uses the @command{rsh} and @command{rcp} commands to connect | |
876 | to the remote machine and transfer files. This is probably the fastest | |
877 | connection method available. | |
878 | ||
879 | ||
880 | @item @option{scp} --- @command{ssh} and @command{scp} | |
92eeeafc KG |
881 | @cindex method scp |
882 | @cindex scp method | |
e28e4d20 KG |
883 | @cindex scp (with scp method) |
884 | @cindex ssh (with scp method) | |
fb7933a3 KG |
885 | |
886 | Using @command{ssh} to connect to the remote host and @command{scp} to | |
887 | transfer files between the machines is the best method for securely | |
888 | connecting to a remote machine and accessing files. | |
889 | ||
890 | The performance of this option is also quite good. It may be slower than | |
891 | the inline methods when you often open and close small files however. | |
892 | The cost of the cryptographic handshake at the start of an @command{scp} | |
893 | session can begin to absorb the advantage that the lack of encoding and | |
894 | decoding presents. | |
895 | ||
92eeeafc | 896 | All the @command{ssh} based methods support the kludgy @samp{-p} |
8e3a1104 KG |
897 | feature where you can specify a port number to connect to in the host |
898 | name. For example, the host name @file{host#42} tells Tramp to | |
92eeeafc | 899 | specify @samp{-p 42} in the argument list for @command{ssh}. |
8e3a1104 | 900 | |
fb7933a3 KG |
901 | |
902 | @item @option{rsync} --- @command{ssh} and @command{rsync} | |
92eeeafc KG |
903 | @cindex method rsync |
904 | @cindex rsync method | |
e28e4d20 KG |
905 | @cindex rsync (with rsync method) |
906 | @cindex ssh (with rsync method) | |
fb7933a3 KG |
907 | |
908 | Using the @command{ssh} command to connect securely to the remote | |
909 | machine and the @command{rsync} command to transfer files is almost | |
910 | identical to the @option{scp} method. | |
911 | ||
912 | While @command{rsync} performs much better than @command{scp} when | |
913 | transferring files that exist on both hosts, this advantage is lost if | |
914 | the file exists only on one side of the connection. | |
915 | ||
916 | The @command{rsync} based method may be considerably faster than the | |
917 | @command{rcp} based methods when writing to the remote system. Reading | |
918 | files to the local machine is no faster than with a direct copy. | |
919 | ||
92eeeafc | 920 | This method supports the @samp{-p} hack. |
8e3a1104 | 921 | |
fb7933a3 KG |
922 | |
923 | @item @option{scpx} --- @command{ssh} and @command{scp} | |
92eeeafc KG |
924 | @cindex method scpx |
925 | @cindex scpx method | |
e28e4d20 KG |
926 | @cindex scp (with scpx method) |
927 | @cindex ssh (with scpx method) | |
928 | @cindex Cygwin (with scpx method) | |
fb7933a3 KG |
929 | |
930 | As you expect, this is similar to @option{scp}, only a little | |
92eeeafc KG |
931 | different. Whereas @option{scp} opens a normal interactive shell on |
932 | the remote host, this option uses @samp{ssh -t -t @var{host} -l | |
933 | @var{user} /bin/sh} to open a connection. This is useful for users | |
934 | where the normal login shell is set up to ask them a number of | |
935 | questions when logging in. This procedure avoids these questions, and | |
936 | just gives @tramp{} a more-or-less `standard' login shell to work | |
937 | with. | |
fb7933a3 KG |
938 | |
939 | This is also useful for Windows users where @command{ssh}, when | |
940 | invoked from an Emacs buffer, tells them that it is not allocating a | |
941 | pseudo tty. When this happens, the login shell is wont to not print | |
92eeeafc KG |
942 | any shell prompt, which confuses @tramp{} mightily. Maybe this |
943 | applies to the Cygwin port of SSH. | |
fb7933a3 | 944 | |
92eeeafc | 945 | This method supports the @samp{-p} hack. |
8e3a1104 | 946 | |
fb7933a3 KG |
947 | |
948 | @item @option{pscp} --- @command{plink} and @command{pscp} | |
92eeeafc KG |
949 | @cindex method pscp |
950 | @cindex pscp method | |
e28e4d20 KG |
951 | @cindex pscp (with pscp method) |
952 | @cindex plink (with pscp method) | |
953 | @cindex PuTTY (with pscp method) | |
fb7933a3 KG |
954 | |
955 | This method is similar to @option{scp}, but it uses the | |
956 | @command{plink} command to connect to the remote host, and it uses | |
957 | @command{pscp} for transferring the files. These programs are part | |
958 | of PuTTY, an SSH implementation for Windows. | |
959 | ||
92eeeafc | 960 | CCC: Does @command{plink} support the @samp{-p} hack? |
8e3a1104 | 961 | |
fb7933a3 KG |
962 | |
963 | @item @option{fcp} --- @command{fsh} and @command{fcp} | |
92eeeafc KG |
964 | @cindex method fcp |
965 | @cindex fcp method | |
e28e4d20 KG |
966 | @cindex fsh (with fcp method) |
967 | @cindex fcp (with fcp method) | |
fb7933a3 KG |
968 | |
969 | This method is similar to @option{scp}, but it uses the @command{fsh} | |
970 | command to connect to the remote host, and it uses @command{fcp} for | |
971 | transferring the files. @command{fsh/fcp} are a front-end for | |
972 | @command{ssh} which allow for reusing the same @command{ssh} session | |
973 | for submitting several commands. This avoids the startup overhead of | |
974 | @command{scp} (which has to establish a secure connection whenever it | |
975 | is called). Note, however, that you can also use one of the inline | |
976 | methods to achieve a similar effect. | |
977 | ||
92eeeafc KG |
978 | This method uses the command @samp{fsh @var{host} -l @var{user} |
979 | /bin/sh -i} to establish the connection, it does not work to just say | |
980 | @command{fsh @var{host} -l @var{user}}. | |
fb7933a3 | 981 | |
e28e4d20 KG |
982 | @cindex method fsh |
983 | @cindex fsh method | |
92eeeafc KG |
984 | There is no inline method using @command{fsh} as the multiplexing |
985 | provided by the program is not very useful in our context. @tramp{} | |
986 | opens just one connection to the remote host and then keeps it open, | |
987 | anyway. | |
988 | ||
989 | @end table | |
fb7933a3 KG |
990 | |
991 | @node Multi-hop Methods | |
992 | @section Connecting to a remote host using multiple hops | |
92eeeafc KG |
993 | @cindex multi-hop methods |
994 | @cindex methods, multi-hop | |
fb7933a3 KG |
995 | |
996 | Sometimes, the methods described before are not sufficient. Sometimes, | |
997 | it is not possible to connect to a remote host using a simple command. | |
998 | For example, if you are in a secured network, you might have to log in | |
999 | to a `bastion host' first before you can connect to the outside world. | |
1000 | Of course, the target host may also require a bastion host. The format | |
1001 | of multi-hop filenames is slightly different than the format of normal | |
1002 | @tramp{} methods. | |
1003 | ||
1004 | A multi-hop file name specifies a method, a number of hops, and a path | |
1005 | name on the remote system. The method specifies how the file is | |
1006 | transferred through the inline connection. The following two multi-hop | |
1007 | methods are available: | |
1008 | ||
92eeeafc | 1009 | @table @asis |
fb7933a3 | 1010 | @item @option{multi} --- base64 encoding with @command{mimencode} |
92eeeafc KG |
1011 | @cindex method multi |
1012 | @cindex multi method | |
e28e4d20 KG |
1013 | @cindex mimencode (with multi method) |
1014 | @cindex base-64 encoding (with multi method) | |
fb7933a3 KG |
1015 | |
1016 | The file is transferred through the connection in base64 encoding. Uses | |
1017 | the @command{mimencode} program for doing encoding and decoding, but | |
1018 | uses an Emacs internal implementation on the local host if available. | |
1019 | ||
1020 | @item @option{multiu} --- use commands @command{uuencode} and @command{uudecode} | |
92eeeafc KG |
1021 | @cindex method multiu |
1022 | @cindex multiu method | |
e28e4d20 | 1023 | @cindex uuencode (with multiu method) |
fb7933a3 KG |
1024 | |
1025 | The file is transferred through the connection in `uu' encoding. Uses | |
1026 | the @command{uuencode} and @command{uudecode} programs for encoding and | |
1027 | decoding, but uses a Lisp implementation for decoding on the local host | |
1028 | if available. | |
1029 | ||
92eeeafc | 1030 | @end table |
fb7933a3 KG |
1031 | |
1032 | Each hop consists of a @dfn{hop method} specification, a user name and a | |
1033 | host name. The following hop methods are (currently) available: | |
1034 | ||
92eeeafc KG |
1035 | @table @option |
1036 | @item telnet | |
1037 | @cindex hop method telnet | |
1038 | @cindex telnet hop method | |
fb7933a3 KG |
1039 | |
1040 | Uses the well-known @command{telnet} program to connect to the host. | |
1041 | Whereas user name and host name are supplied in the file name, the | |
1042 | user is queried for the password. | |
1043 | ||
92eeeafc KG |
1044 | @item rsh |
1045 | @cindex hop method rsh | |
1046 | @cindex rsh hop method | |
fb7933a3 KG |
1047 | |
1048 | This uses @command{rsh} to connect to the host. You do not need to | |
1049 | enter a password unless @command{rsh} explicitly asks for it. | |
1050 | ||
92eeeafc KG |
1051 | @item ssh |
1052 | @cindex hop method ssh | |
1053 | @cindex ssh hop method | |
fb7933a3 KG |
1054 | |
1055 | This uses @command{ssh} to connect to the host. You might have to enter | |
1056 | a password or a pass phrase. | |
1057 | ||
92eeeafc KG |
1058 | @item su |
1059 | @cindex hop method su | |
1060 | @cindex su hop method | |
fb7933a3 KG |
1061 | |
1062 | This method does not actually contact a different host, but it allows | |
1063 | you to become a different user on the host you're currently on. This | |
1064 | might be useful if you want to edit files as root, but the remote host | |
1065 | does not allow remote root logins. In this case you can use | |
1066 | @option{telnet}, @option{rsh} or @option{ssh} to connect to the | |
1067 | remote host as a non-root user, then use an @option{su} hop to become | |
1068 | root. But @option{su} need not be the last hop in a sequence, you could | |
1069 | also use it somewhere in the middle, if the need arises. | |
1070 | ||
1071 | Even though you @emph{must} specify both user and host with a | |
1072 | @option{su} hop, the host name is ignored and only the user name is | |
1073 | used. | |
1074 | ||
92eeeafc KG |
1075 | @item sudo |
1076 | @cindex hop method sudo | |
1077 | @cindex sudo hop method | |
fb7933a3 KG |
1078 | |
1079 | This is similar to the @option{su} hop, except that it uses | |
1080 | @command{sudo} rather than @command{su} to become a different user. | |
1081 | ||
92eeeafc | 1082 | @end table |
fb7933a3 | 1083 | |
92eeeafc KG |
1084 | Some people might wish to use port forwarding with @command{ssh} or |
1085 | maybe they have to use a nonstandard port. This can be accomplished | |
1086 | by putting a stanza in @file{~/.ssh/config} for the account which | |
1087 | specifies a different port number for a certain host name. But it can | |
1088 | also be accomplished within Tramp, by adding a multi-hop method. For | |
1089 | example: | |
fb7933a3 KG |
1090 | |
1091 | @lisp | |
1092 | (add-to-list 'tramp-multi-connection-function-alist | |
1093 | '("sshf" tramp-multi-connect-rlogin "ssh %h -l %u -p 4400%n")) | |
1094 | @end lisp | |
1095 | ||
1096 | Now you can use a @code{sshf} hop which connects to port 4400 instead of | |
1097 | the standard port. | |
1098 | ||
1099 | ||
1100 | @node Default Method | |
1101 | @section Selecting a default method | |
92eeeafc | 1102 | @cindex default method |
fb7933a3 | 1103 | |
92eeeafc | 1104 | @vindex tramp-default-method |
fb7933a3 KG |
1105 | When you select an appropriate transfer method for your typical usage |
1106 | you should set the variable @var{tramp-default-method} to reflect that | |
92eeeafc | 1107 | choice. This variable controls which method will be used when a method |
fb7933a3 KG |
1108 | is not specified in the @tramp{} file path. For example: |
1109 | ||
1110 | @lisp | |
1111 | (setq tramp-default-method "scp") | |
1112 | @end lisp | |
1113 | ||
92eeeafc KG |
1114 | @vindex tramp-default-method-alist |
1115 | You can also specify different methods for certain user/host | |
1116 | combinations, via the variable @var{tramp-default-method-alist}. For | |
1117 | example, the following two lines specify to use the @option{sm} | |
1118 | method for all user names matching @samp{john} and the @option{rsync} | |
1119 | method for all host names matching @samp{lily}. The third line | |
1120 | specifies to use the @option{sum} method for the user @samp{root} on | |
1121 | the machine @samp{localhost}. | |
1122 | ||
1123 | @lisp | |
1124 | (add-to-list 'tramp-default-method-alist '("" "john" "sm")) | |
1125 | (add-to-list 'tramp-default-method-alist '("lily" "" "rsync")) | |
1126 | (add-to-list 'tramp-default-method-alist | |
1127 | '("\\`root\\'" "\\`localhost\\'" "sum")) | |
1128 | @end lisp | |
1129 | ||
1130 | @noindent | |
1131 | See the documentation for the variable | |
1132 | @var{tramp-default-method-alist} for more details. | |
1133 | ||
fb7933a3 KG |
1134 | External transfer methods are normally preferable to inline transfer |
1135 | methods, giving better performance. They may not be useful if you use | |
1136 | many remote machines where you cannot log in without a password. | |
1137 | ||
1138 | @xref{Inline methods}. | |
1139 | @xref{External transfer methods}. | |
1140 | @xref{Multi-hop Methods}. | |
1141 | ||
1142 | Another consideration with the selection of transfer methods is the | |
1143 | environment you will use them in and, especially when used over the | |
1144 | Internet, the security implications of your preferred method. | |
1145 | ||
1146 | The @command{rsh} and @command{telnet} methods send your password as | |
1147 | plain text as you log in to the remote machine, as well as transferring | |
1148 | the files in such a way that the content can easily be read from other | |
1149 | machines. | |
1150 | ||
1151 | If you need to connect to remote systems that are accessible from the | |
1152 | Internet, you should give serious thought to using @command{ssh} based | |
1153 | methods to connect. These provide a much higher level of security, | |
1154 | making it a non-trivial exercise for someone to obtain your password or | |
1155 | read the content of the files you are editing. | |
1156 | ||
1157 | @node Customizing Methods | |
1158 | @section Using Non-Standard Methods | |
92eeeafc KG |
1159 | @cindex customizing methods |
1160 | @cindex using non-standard methods | |
1161 | @cindex create your own methods | |
fb7933a3 KG |
1162 | |
1163 | There is a variable @code{tramp-methods} which you can change if the | |
1164 | predefined methods don't seem right. | |
1165 | ||
1166 | For the time being, I'll refer you to the Lisp documentation of that | |
1167 | variable, accessible with @kbd{C-h v tramp-methods @key{RET}}. | |
1168 | ||
1169 | ||
1170 | @node Remote Programs | |
1171 | @section How @tramp{} finds and uses programs on the remote machine. | |
1172 | ||
1173 | @tramp{} depends on a number of programs on the remote host in order to | |
1174 | function, including @command{ls}, @command{test}, @command{find} and | |
1175 | @command{cat}. | |
1176 | ||
1177 | In addition to these required tools, there are various tools that may be | |
1178 | required based on the connection method. See @ref{Inline methods} and | |
1179 | @ref{External transfer methods} for details on these. | |
1180 | ||
1181 | Certain other tools, such as @command{perl} (or @command{perl5}) and | |
1182 | @command{grep} will be used if they can be found. When they are | |
1183 | available, they are used to improve the performance and accuracy of | |
1184 | remote file access. | |
1185 | ||
92eeeafc | 1186 | @vindex tramp-remote-path |
fb7933a3 KG |
1187 | When @tramp{} connects to the remote machine, it searches for the |
1188 | programs that it can use. The variable @var{tramp-remote-path} controls | |
1189 | the directories searched on the remote machine. | |
1190 | ||
1191 | By default, this is set to a reasonable set of defaults for most | |
1192 | machines. It is possible, however, that your local (or remote ;) system | |
1193 | administrator has put the tools you want in some obscure local | |
1194 | directory. | |
1195 | ||
1196 | In this case, you can still use them with @tramp{}. You simply need to | |
1197 | add code to your @file{.emacs} to add the directory to the remote path. | |
1198 | This will then be searched by @tramp{} when you connect and the software | |
1199 | found. | |
1200 | ||
1201 | To add a directory to the remote search path, you could use code such | |
1202 | as: | |
1203 | ||
1204 | @example | |
1205 | (require 'tramp) @i{; @tramp{} must be loaded before this} | |
1206 | @i{; happens.} | |
1207 | ||
92eeeafc KG |
1208 | @i{; We have @command{perl} in "/usr/local/perl/bin"} |
1209 | (add-to-list 'tramp-remote-path "/usr/local/perl/bin") | |
fb7933a3 KG |
1210 | @end example |
1211 | ||
1212 | @node Remote shell setup | |
1213 | @comment node-name, next, previous, up | |
1214 | @section Remote shell setup hints | |
92eeeafc | 1215 | @cindex remote shell setup |
e28e4d20 KG |
1216 | @cindex @file{.profile} file |
1217 | @cindex @file{.login} file | |
92eeeafc | 1218 | @cindex shell init files |
fb7933a3 KG |
1219 | |
1220 | As explained in the @ref{Overview} section, @tramp{} connects to the | |
1221 | remote host and talks to the shell it finds there. Of course, when you | |
1222 | log in, the shell executes its init files. Suppose your init file | |
1223 | requires you to enter the birthdate of your mother; clearly @tramp{} | |
1224 | does not know this and hence fails to log you in to that host. | |
1225 | ||
1226 | There are different possible strategies for pursuing this problem. One | |
1227 | strategy is to enable @tramp{} to deal with all possible situations. | |
1228 | This is a losing battle, since it is not possible to deal with | |
1229 | @emph{all} situations. The other strategy is to require you to set up | |
1230 | the remote host such that it behaves like @tramp{} expect. This might | |
1231 | be inconvenient because you have to invest a lot of effort into shell | |
1232 | setup before you can begin to use @tramp{}. | |
1233 | ||
1234 | The package, therefore, pursues a combined approach. It tries to figure | |
1235 | out some of the more common setups, and only requires you to avoid | |
1236 | really exotic stuff. For example, it looks through a list of | |
1237 | directories to find some programs on the remote host. And also, it | |
1238 | knows that it is not obvious how to check whether a file exist, and | |
1239 | therefore it tries different possibilities. (On some hosts and shells, | |
1240 | the command @code{test -e} does the trick, on some hosts the shell | |
1241 | builtin doesn't work but the program @code{/usr/bin/test -e} or | |
1242 | @code{/bin/test -e} works. And on still other hosts, @code{ls -d} is | |
1243 | the right way to do this.) | |
1244 | ||
1245 | Below you find a discussion of a few things that @tramp{} does not deal | |
1246 | with, and that you therefore have to set up correctly. | |
1247 | ||
92eeeafc KG |
1248 | @table @asis |
1249 | @item @var{shell-prompt-pattern} | |
fb7933a3 | 1250 | @vindex shell-prompt-pattern |
92eeeafc | 1251 | |
fb7933a3 KG |
1252 | After logging in to the remote host, @tramp{} has to wait for the remote |
1253 | shell startup to finish before it can send commands to the remote | |
1254 | shell. The strategy here is to wait for the shell prompt. In order to | |
1255 | recognize the shell prompt, the variable @code{shell-prompt-pattern} has | |
1256 | to be set correctly to recognize the shell prompt on the remote host. | |
1257 | ||
83fa16cf KG |
1258 | Note that Tramp requires the match for @code{shell-prompt-pattern} to |
1259 | be at the end of the buffer. Many people have something like the | |
1260 | following as the value for the variable: @code{"^[^>$][>$] *"}. Now | |
1261 | suppose your shell prompt is @code{a <b> c $ }. In this case, Tramp | |
1262 | recognizes the @code{>} character as the end of the prompt, but it is | |
1263 | not at the end of the buffer. | |
1264 | ||
fb7933a3 | 1265 | @item @code{tset} and other questions |
92eeeafc KG |
1266 | @cindex Unix command tset |
1267 | @cindex tset Unix command | |
fb7933a3 KG |
1268 | |
1269 | Some people invoke the @code{tset} program from their shell startup | |
1270 | scripts which asks the user about the terminal type of the shell. Maybe | |
1271 | some shells ask other questions when they are started. @tramp{} does | |
1272 | not know how to answer these questions. (A facility for enabling | |
1273 | @tramp{} to answer these questions is planned for some future version, | |
1274 | but don't hold your breath.) | |
1275 | ||
1276 | Therefore, you should take care that the shell does not ask any | |
1277 | questions when invoked from @tramp{}. You can do this by checking the | |
1278 | @code{TERM} environment variable, it will be set to @code{dumb} when | |
1279 | connecting. | |
1280 | ||
1281 | @vindex tramp-terminal-type | |
1282 | The variable @code{tramp-terminal-type} can be used to change this value | |
1283 | @code{dumb}. | |
1284 | ||
92eeeafc | 1285 | @end table |
fb7933a3 KG |
1286 | |
1287 | ||
1288 | @node Windows setup hints | |
1289 | @section Issues with Cygwin ssh | |
e28e4d20 | 1290 | @cindex Cygwin, issues |
fb7933a3 KG |
1291 | |
1292 | This section needs a lot of work! Please help. | |
1293 | ||
92eeeafc KG |
1294 | @cindex method smx with Cygwin |
1295 | @cindex smx method with Cygwin | |
fb7933a3 KG |
1296 | If you use the Cygwin installation of ssh (you have to explicitly select |
1297 | it in the installer), then it should work out of the box to just select | |
1298 | @code{smx} as the connection method. You can find information about | |
1299 | setting up Cygwin in their FAQ at @uref{http://cygwin.com/faq/}. | |
1300 | ||
1301 | ||
1302 | @node Usage | |
1303 | @chapter Using @tramp | |
92eeeafc | 1304 | @cindex using @tramp |
fb7933a3 KG |
1305 | |
1306 | Once you have installed @tramp{} it will operate fairly transparently. You | |
1307 | will be able to access files on any remote machine that you can log in | |
1308 | to as though they were local. | |
1309 | ||
1310 | Files are specified to @tramp{} using a formalized syntax specifying the | |
92eeeafc KG |
1311 | details of the system to connect to. This is similar to the syntax used |
1312 | by the @command{EFS} and @command{Ange-FTP} packages. | |
fb7933a3 KG |
1313 | |
1314 | ||
1315 | @menu | |
1316 | * Filename Syntax:: @tramp{} filename conventions. | |
1317 | * Multi-hop filename syntax:: Multi-hop filename conventions | |
1318 | * Dired:: Dired and filename completion. | |
1319 | @end menu | |
1320 | ||
1321 | ||
1322 | @node Filename Syntax | |
1323 | @section @tramp{} filename conventions | |
92eeeafc KG |
1324 | @cindex filename syntax |
1325 | @cindex filename examples | |
fb7933a3 | 1326 | |
f37fc5a7 KG |
1327 | On Emacs, the Ange-FTP and Tramp filenames use a unified syntax. On |
1328 | XEmacs, EFS and Tramp use different formats for the filenames. | |
1329 | Therefore, the following will describe the Emacs and XEmacs cases | |
1330 | separately. | |
fb7933a3 | 1331 | |
f37fc5a7 KG |
1332 | On Emacs, to access the file @var{path} on the remote machine |
1333 | @var{machine} you would specify the filename | |
1334 | @file{/@var{machine}:@var{path}}. This will connect to @var{machine} | |
1335 | and transfer the file using the default method. @xref{Default | |
1336 | Method}. On XEmacs, use @file{/[@var{machine}]@var{path}}. (The | |
1337 | square brackets are part of the file name.) | |
1338 | ||
1339 | Some examples of @tramp{} filenames are shown below. In each case, | |
1340 | the Emacs-style filename is shown first, then the XEmacs-style | |
1341 | filename. | |
fb7933a3 KG |
1342 | |
1343 | @table @file | |
f37fc5a7 KG |
1344 | @item /melancholia:.emacs |
1345 | @itemx /[melancholia].emacs | |
fb7933a3 KG |
1346 | Edit the file @file{.emacs} in your home directory on the machine |
1347 | @code{melancholia}. | |
1348 | ||
f37fc5a7 KG |
1349 | @item /melancholia.danann.net:.emacs |
1350 | @itemx /[melancholia.danann.net].emacs | |
fb7933a3 KG |
1351 | This edits the same file, using the fully qualified domain name of |
1352 | the machine. | |
1353 | ||
f37fc5a7 KG |
1354 | @item /melancholia:~/.emacs |
1355 | @itemx /[melancholia]~/.emacs | |
fb7933a3 KG |
1356 | This also edits the same file --- the @file{~} is expanded to your |
1357 | home directory on the remote machine, just like it is locally. | |
1358 | ||
f37fc5a7 KG |
1359 | @item /melancholia:~daniel/.emacs |
1360 | @itemx /[melancholia]~daniel/.emacs | |
fb7933a3 KG |
1361 | This edits the file @file{.emacs} in the home directory of the user |
1362 | @code{daniel} on the machine @code{melancholia}. The @file{~<user>} | |
1363 | construct is expanded to the home directory of that user on the remote | |
1364 | machine. | |
1365 | ||
f37fc5a7 KG |
1366 | @item /melancholia:/etc/squid.conf |
1367 | @itemx /[melancholia]/etc/squid.conf | |
fb7933a3 KG |
1368 | This edits the file @file{/etc/squid.conf} on the machine |
1369 | @code{melancholia}. | |
1370 | ||
1371 | @end table | |
1372 | ||
fb7933a3 KG |
1373 | Unless you specify a different name to use, @tramp{} will use the current |
1374 | local user name as the remote user name to log in with. If you need to | |
1375 | log in as a different user, you can specify the user name as part of the | |
1376 | filename. | |
1377 | ||
f37fc5a7 KG |
1378 | On Emacs, to log in to the remote machine as a specific user, you use |
1379 | the syntax @file{/@var{user}@@@var{machine}:/path/to.file}. On | |
1380 | XEmacs, use @file{/[@var{user}@@@var{machine}]/path/to.file}. That | |
1381 | means that connecting to @code{melancholia} as @code{daniel} and | |
1382 | editing @file{.emacs} in your home directory you would specify | |
1383 | @file{/daniel@@melancholia:.emacs} on Emacs and | |
1384 | @file{/[daniel@@melancholia].emacs} on XEmacs. | |
fb7933a3 KG |
1385 | |
1386 | ||
1387 | It is also possible to specify other file transfer methods | |
f37fc5a7 KG |
1388 | (@pxref{Default Method}) as part of the filename. On Emacs, this is |
1389 | done by puttig the method before the user and host name, as in | |
1390 | @file{/@var{method}:} (note the trailing colon). On XEmacs, it is | |
1391 | done by replacing the initial @file{/[} with @file{/[<method>/}. | |
1392 | (Note the trailing slash!) The user, machine and file specification | |
1393 | remain the same. | |
fb7933a3 | 1394 | |
f37fc5a7 KG |
1395 | So, to connect to the machine @code{melancholia} as @code{daniel}, |
1396 | using the @option{su} method to transfer files, and edit @file{.emacs} | |
1397 | in my home directory I would specify the filename | |
1398 | @file{/su:daniel@@melancholia:.emacs} on Emacs and | |
1399 | @file{/[su/daniel@@melancholia].emacs} on XEmacs. | |
fb7933a3 KG |
1400 | |
1401 | ||
1402 | @node Multi-hop filename syntax | |
1403 | @section Multi-hop filename conventions | |
92eeeafc KG |
1404 | @cindex filename syntax for multi-hop files |
1405 | @cindex multi-hop filename syntax | |
fb7933a3 KG |
1406 | |
1407 | The syntax of multi-hop file names is necessarily slightly different | |
1408 | than the syntax of other @tramp{} file names. Here's an example multi-hop | |
f37fc5a7 | 1409 | file name, first in Emacs syntax and then in XEmacs syntax: |
fb7933a3 | 1410 | |
f37fc5a7 | 1411 | @file{/multi:rsh:out@@gate:telnet:kai@@real.host:/path/to.file} |
fb7933a3 KG |
1412 | @file{/[multi/rsh:out@@gate/telnet:kai@@real.host]/path/to.file} |
1413 | ||
1414 | This is quite a mouthful. So let's go through it step by step. The | |
f37fc5a7 KG |
1415 | file name consists of three parts. On Emacs, the parts are separated |
1416 | by colons, on XEmacs they are separated by slashes and square | |
1417 | brackets. The first part is @file{/multi:} (or @file{/[multi}), the | |
1418 | method specification. The second part is | |
1419 | @file{rsh:out@@gate:telnet:kai@@real.host} (or | |
1420 | @file{rsh:out@@gate/telnet:kai@@real.host}) and specifies the hops. | |
1421 | (Yes, on Emacs the second part may contain even more colons, so that's why | |
1422 | this file name has more than two colons in it.) The final part is | |
1423 | @file{/path/to.file} and specifies the file name on the remote host. | |
fb7933a3 KG |
1424 | |
1425 | The first part and the final part should be clear. @ref{Multi-hop | |
1426 | Methods}, for a list of alternatives for the method specification. | |
1427 | ||
1428 | The second part can be subdivided again into components, so-called hops. | |
1429 | In the above file name, there are two hops, @file{rsh:out@@gate} and | |
1430 | @file{telnet:kai@@real.host}. | |
1431 | ||
1432 | Each hop can @emph{again} be subdivided into (three) components, the | |
1433 | @dfn{hop method}, the @dfn{user name} and the @dfn{host name}. The | |
1434 | meaning of the second and third component should be clear, and the hop | |
1435 | method says what program to use to perform that hop. | |
1436 | ||
1437 | The first hop, @file{rsh:out@@gate}, says to use @command{rsh} to log in | |
1438 | as user @code{out} to the host @code{gate}. Starting at that host, the | |
1439 | second hop, @file{telnet:kai@@real.host}, says to use @command{telnet} | |
1440 | to log in as user @code{kai} to host @code{real.host}. | |
1441 | ||
1442 | @xref{Multi-hop Methods}, for a list of possible hop method values. The | |
1443 | variable @var{tramp-multi-connection-function-alist} contains the list of | |
1444 | possible hop methods and information on how to execute them, should you | |
1445 | want to add your own. | |
1446 | ||
1447 | ||
1448 | @node Dired | |
1449 | @section Dired and filename completion | |
92eeeafc KG |
1450 | @cindex dired |
1451 | @cindex filename completion | |
fb7933a3 KG |
1452 | |
1453 | @tramp{} works transparently with dired, enabling you to use this powerful | |
1454 | file management tool to manage files on any machine you have access to | |
1455 | over the Internet. | |
1456 | ||
1457 | Filename completion also works with @tramp{} for files on remote machines | |
1458 | although there is no completion for user names or machine names at this | |
1459 | stage. | |
1460 | ||
1461 | As filename completion needs to fetch the listing of files from the | |
92eeeafc | 1462 | remote machine, this feature is sometimes fairly slow. As @tramp{} does not |
fb7933a3 KG |
1463 | yet cache the results of directory listing, there is no gain in |
1464 | performance the second time you complete filenames. | |
1465 | ||
1466 | If you need to browse a directory tree, Dired is a better choice, at | |
92eeeafc | 1467 | present, than filename completion. Dired has its own cache mechanism |
fb7933a3 KG |
1468 | and will only fetch the directory listing once. |
1469 | ||
1470 | ||
1471 | @node Bug Reports | |
1472 | @chapter Reporting Bugs and Problems | |
92eeeafc | 1473 | @cindex bug reports |
fb7933a3 KG |
1474 | |
1475 | Bugs and problems with @tramp{} are actively worked on by the development | |
1476 | team. Feature requests and suggestions are also more than welcome. | |
1477 | ||
1478 | The @tramp{} mailing list is a great place to get information on working | |
1479 | with @tramp{}, solving problems and general discussion and advice on topics | |
1480 | relating to the package. | |
1481 | ||
1482 | The mailing list is at @email{tramp-devel@@mail.freesoftware.fsf.org}. | |
1483 | Messages sent to this address go to all the subscribers. This is | |
1484 | @emph{not} the address to send subscription requests to. | |
1485 | ||
1486 | For help on subscribing to the list, send mail to the administrative | |
1487 | address, @email{tramp-devel-request@@mail.freesoftware.fsf.org}, with the | |
1488 | subject @samp{help}. | |
1489 | ||
1490 | To report a bug in @tramp{}, you should execute @kbd{M-x tramp-bug}. This | |
1491 | will automatically generate a buffer with the details of your system and | |
1492 | @tramp{} version. | |
1493 | ||
1494 | When submitting a bug report, please try to describe in excruciating | |
1495 | detail the steps required to reproduce the problem, the setup of the | |
1496 | remote machine and any special conditions that exist. | |
1497 | ||
1498 | If you can identify a minimal test case that reproduces the problem, | |
1499 | include that with your bug report. This will make it much easier for the | |
1500 | development team to analyze and correct the problem. | |
1501 | ||
1502 | @node Frequently Asked Questions | |
1503 | @chapter Frequently Asked Questions | |
92eeeafc KG |
1504 | @cindex frequently asked questions |
1505 | @cindex FAQ | |
fb7933a3 KG |
1506 | |
1507 | @itemize @bullet | |
92eeeafc KG |
1508 | @item |
1509 | Where can I get the latest @tramp{}? | |
fb7933a3 KG |
1510 | |
1511 | @tramp{} is available at | |
1512 | @uref{ftp://ls6-ftp.cs.uni-dortmund.de/pub/src/emacs/tramp.tar.gz}. | |
1513 | There is also a Savannah project page, at | |
1514 | @uref{https://savannah.gnu.org/projects/tramp/}. | |
1515 | ||
1516 | ||
92eeeafc KG |
1517 | @item |
1518 | Which systems does it work on? | |
fb7933a3 KG |
1519 | |
1520 | The package has been used successfully on Emacs 20 and Emacs 21, as well | |
1521 | as XEmacs 21. XEmacs 20 is more problematic, see the notes in | |
1522 | @file{tramp.el}. I don't think anybody has really tried it on Emacs 19. | |
1523 | ||
1524 | The package was intended to work on Unix, and it really expects a | |
1525 | Unix-like system on the remote end, but some people seemed to have some | |
1526 | success getting it to work on NT Emacs. | |
1527 | ||
1528 | There are some informations on Tramp on NT at the following URL; many | |
1529 | thanks to Joe Stoy for providing the information: | |
1530 | @uref{ftp://ftp.comlab.ox.ac.uk/tmp/Joe.Stoy/} | |
1531 | ||
1532 | The above mostly contains patches to old ssh versions; Tom Roche has a | |
1533 | Web page with instructions: | |
1534 | @uref{http://www4.ncsu.edu/~tlroche/plinkTramp.html} | |
1535 | ||
1536 | ??? Is the XEmacs info correct? | |
1537 | ||
1538 | ??? Can somebody provide some information for getting it to work on NT | |
1539 | Emacs? I think there was some issue with @command{ssh}? | |
1540 | ||
1541 | ||
92eeeafc KG |
1542 | @item |
1543 | I can't stop EFS starting with XEmacs | |
fb7933a3 KG |
1544 | |
1545 | Not all the older versions of @tramp{} supported XEmacs correctly. The | |
1546 | first thing to do is to make sure that you have the latest version of | |
1547 | @tramp{} installed. | |
1548 | ||
1549 | If you do, please try and find out exactly the conditions required for | |
1550 | the @code{EFS} handlers to fire. If you can, putting a breakpoint on | |
1551 | @code{efs-ftp-path} and sending in the stack trace along with your bug | |
1552 | report would make it easier for the developers to work out what is going | |
1553 | wrong. | |
1554 | ||
1555 | ||
92eeeafc KG |
1556 | @item |
1557 | File name completion does not work with @tramp{} | |
fb7933a3 KG |
1558 | |
1559 | When you log in to the remote machine, do you see the output of | |
1560 | @command{ls} in color? If so, this may be the cause of your problems. | |
1561 | ||
1562 | @command{ls} outputs @acronym{ANSI} escape sequences that your terminal | |
1563 | emulator interprets to set the colors. These escape sequences will | |
1564 | confuse @tramp{} however. | |
1565 | ||
1566 | In your @file{.bashrc}, @file{.profile} or equivalent on the remote | |
1567 | machine you probably have an alias configured that adds the option | |
1568 | @option{--color=yes} or @option{--color=auto}. | |
1569 | ||
1570 | You should remove that alias and ensure that a new login @emph{does not} | |
1571 | display the output of @command{ls} in color. If you still cannot use | |
1572 | filename completion, report a bug to the @tramp{} developers. | |
1573 | ||
1574 | ||
92eeeafc KG |
1575 | @item |
1576 | File name completion does not work in large directories | |
fb7933a3 KG |
1577 | |
1578 | @tramp{} uses globbing for some operations. (Globbing means to use the | |
1579 | shell to expand wildcards such as `*.c'.) This might create long | |
1580 | command lines, especially in directories with many files. Some shell | |
1581 | choke on long command lines, or don't cope well with the globbing | |
1582 | itself. | |
1583 | ||
1584 | If you have a large directory on the remote end, you may wish to execute | |
92eeeafc | 1585 | a command like @samp{ls -d * ..?* > /dev/null} and see if it hangs. |
fb7933a3 KG |
1586 | Note that you must first start the right shell, which might be |
1587 | @command{/bin/sh}, @command{ksh} or @command{bash}, depending on which | |
1588 | of those supports tilde expansion. | |
1589 | ||
1590 | ||
92eeeafc KG |
1591 | @item |
1592 | What kinds of systems does @tramp{} work on | |
fb7933a3 KG |
1593 | |
1594 | @tramp{} really expects the remote system to be a Unix-like system. The | |
1595 | local system should preferably be Unix-like, as well, but @tramp{} might | |
1596 | work on NT with some tweaking. | |
1597 | ||
1598 | ||
92eeeafc KG |
1599 | @item |
1600 | How can I get notified when @tramp{} file transfers are complete? | |
fb7933a3 KG |
1601 | |
1602 | The following snippet can be put in your @file{~/.emacs} file. It makes | |
1603 | Emacs beep after reading from or writing to the remote host. | |
1604 | ||
1605 | @lisp | |
1606 | (defadvice tramp-handle-write-region | |
1607 | (after tramp-write-beep-advice activate) | |
1608 | " make tramp beep after writing a file." | |
1609 | (interactive) | |
1610 | (beep)) | |
1611 | (defadvice tramp-handle-do-copy-or-rename-file | |
1612 | (after tramp-copy-beep-advice activate) | |
1613 | " make tramp beep after copying a file." | |
1614 | (interactive) | |
1615 | (beep)) | |
1616 | (defadvice tramp-handle-insert-file-contents | |
1617 | (after tramp-copy-beep-advice activate) | |
1618 | " make tramp beep after copying a file." | |
1619 | (interactive) | |
1620 | (beep)) | |
1621 | @end lisp | |
1622 | ||
1623 | ||
92eeeafc KG |
1624 | @item |
1625 | There's this @file{~/.sh_history} file on the remote host which keeps | |
1626 | growing and growing. What's that? | |
fb7933a3 KG |
1627 | |
1628 | Sometimes, @tramp{} starts @code{ksh} on the remote host for tilde | |
1629 | expansion. Maybe @code{ksh} saves the history by default. @tramp{} | |
1630 | tries to turn off saving the history, but maybe you have to help. For | |
1631 | example, you could put this in your @file{.kshrc}: | |
1632 | ||
1633 | @example | |
1634 | if [ -f $HOME/.sh_history ] ; then | |
1635 | /bin/rm $HOME/.sh_history | |
1636 | fi | |
1637 | if [ "$@{HISTFILE-unset@}" != "unset" ] ; then | |
1638 | unset HISTFILE | |
1639 | fi | |
1640 | if [ "$@{HISTSIZE-unset@}" != "unset" ] ; then | |
1641 | unset HISTSIZE | |
1642 | fi | |
1643 | @end example | |
1644 | ||
1645 | @end itemize | |
1646 | ||
1647 | ||
1648 | @c For the developer | |
1649 | @node Version Control | |
1650 | @chapter The inner workings of remote version control | |
1651 | ||
92eeeafc | 1652 | Unlike EFS and Ange-FTP, @tramp{} has full shell access to the remote |
fb7933a3 KG |
1653 | machine. This makes it possible to provide version control for files |
1654 | accessed under @tramp{}. | |
1655 | ||
1656 | The actual version control binaries must be installed on the remote | |
1657 | machine, accessible in the directories specified in | |
1658 | @var{tramp-remote-path}. | |
1659 | ||
1660 | This transparent integration with the version control systems is one of | |
1661 | the most valuable features provided by @tramp{}, but it is far from perfect. | |
1662 | Work is ongoing to improve the transparency of the system. | |
1663 | ||
1664 | @menu | |
1665 | * Version Controlled Files:: Determining if a file is under version control. | |
1666 | * Remote Commands:: Executing the version control commands on the remote machine. | |
1667 | * Changed workfiles:: Detecting if the working file has changed. | |
1668 | * Checking out files:: Bringing the workfile out of the repository. | |
1669 | * Miscellaneous Version Control:: Things related to Version Control that don't fit elsewhere | |
1670 | @end menu | |
1671 | ||
1672 | ||
1673 | @node Version Controlled Files | |
1674 | @section Determining if a file is under version control | |
1675 | ||
1676 | The VC package uses the existence of on-disk revision control master | |
1677 | files to determine if a given file is under revision control. These file | |
1678 | tests happen on the remote machine through the standard @tramp{} mechanisms. | |
1679 | ||
1680 | ||
1681 | @node Remote Commands | |
1682 | @section Executing the version control commands on the remote machine | |
1683 | ||
1684 | There are no hooks provided by VC to allow intercepting of the version | |
1685 | control command execution. The calls occur through the | |
1686 | @code{call-process} mechanism, a function that is somewhat more | |
1687 | efficient than the @code{shell-command} function but that does not | |
1688 | provide hooks for remote execution of commands. | |
1689 | ||
1690 | To work around this, the functions @code{vc-do-command} and | |
1691 | @code{vc-simple-command} have been advised to intercept requests for | |
1692 | operations on files accessed via @tramp{}. | |
1693 | ||
1694 | In the case of a remote file, the @code{shell-command} interface is | |
1695 | used, with some wrapper code, to provide the same functionality on the | |
1696 | remote machine as would be seen on the local machine. | |
1697 | ||
1698 | ||
1699 | @node Changed workfiles | |
1700 | @section Detecting if the working file has changed | |
1701 | ||
1702 | As there is currently no way to get access to the mtime of a file on a | |
1703 | remote machine in a portable way, the @code{vc-workfile-unchanged-p} | |
1704 | function is advised to call an @tramp{} specific function for remote files. | |
1705 | ||
1706 | The @code{tramp-vc-workfile-unchanged-p} function uses the functioning VC | |
1707 | diff functionality to determine if any changes have occurred between the | |
1708 | workfile and the version control master. | |
1709 | ||
1710 | This requires that a shell command be executed remotely, a process that | |
1711 | is notably heavier-weight than the mtime comparison used for local | |
1712 | files. Unfortunately, unless a portable solution to the issue is found, | |
1713 | this will remain the cost of remote version control. | |
1714 | ||
1715 | ||
1716 | @node Checking out files | |
1717 | @section Bringing the workfile out of the repository | |
1718 | ||
1719 | VC will, by default, check for remote files and refuse to act on them | |
1720 | when checking out files from the repository. To work around this | |
1721 | problem, the function @code{vc-checkout} knows about @tramp{} files and | |
1722 | allows version control to occur. | |
1723 | ||
1724 | ||
1725 | @node Miscellaneous Version Control | |
1726 | @section Things related to Version Control that don't fit elsewhere | |
1727 | ||
1728 | Minor implementation details, &c. | |
1729 | ||
1730 | @menu | |
1731 | * Remote File Ownership:: How VC determines who owns a workfile. | |
1732 | * Back-end Versions:: How VC determines what release your RCS is. | |
1733 | @end menu | |
1734 | ||
1735 | ||
1736 | @node Remote File Ownership | |
1737 | @subsection How VC determines who owns a workfile | |
1738 | ||
1739 | Emacs provides the @code{user-full-name} function to return the login name | |
1740 | of the current user as well as mapping from arbitrary user id values | |
1741 | back to login names. The VC code uses this functionality to map from the | |
1742 | uid of the owner of a workfile to the login name in some circumstances. | |
1743 | ||
1744 | This will not, for obvious reasons, work if the remote system has a | |
1745 | different set of logins. As such, it is necessary to delegate to the | |
1746 | remote machine the job of determining the login name associated with a | |
1747 | uid. | |
1748 | ||
1749 | Unfortunately, with the profusion of distributed management systems such | |
1750 | as @code{NIS}, @code{NIS+} and @code{NetInfo}, there is no simple, | |
1751 | reliable and portable method for performing this mapping. | |
1752 | ||
1753 | Thankfully, the only place in the VC code that depends on the mapping of | |
1754 | a uid to a login name is the @code{vc-file-owner} function. This returns | |
1755 | the login of the owner of the file as a string. | |
1756 | ||
1757 | This function has been advised to use the output of @command{ls} on the | |
1758 | remote machine to determine the login name, delegating the problem of | |
1759 | mapping the uid to the login to the remote system which should know more | |
1760 | about it than I do. | |
1761 | ||
1762 | ||
1763 | @node Back-end Versions | |
1764 | @subsection How VC determines what release your RCS is | |
1765 | ||
1766 | VC needs to know what release your revision control binaries you are | |
1767 | running as not all features VC supports are available with older | |
1768 | versions of @command{rcs(1)}, @command{cvs(1)} or @command{sccs(1)}. | |
1769 | ||
1770 | The default implementation of VC determines this value the first time it | |
1771 | is needed and then stores the value globally to avoid the overhead of | |
1772 | executing a process and parsing its output each time the information is | |
1773 | needed. | |
1774 | ||
1775 | Unfortunately, life is not quite so easy when remote version control | |
1776 | comes into the picture. Each remote machine may have a different version | |
1777 | of the version control tools and, while this is painful, we need to | |
1778 | ensure that unavailable features are not used remotely. | |
1779 | ||
1780 | To resolve this issue, @tramp{} currently takes the sledgehammer | |
1781 | approach of making the release values of the revision control tools | |
1782 | local to each @tramp{} buffer, forcing VC to determine these values | |
1783 | again each time a new file is visited. | |
1784 | ||
1785 | This has, quite obviously, some performance implications. Thankfully, | |
1786 | most of the common operations performed by VC do not actually require | |
1787 | that the remote version be known. This makes the problem far less | |
1788 | apparent. | |
1789 | ||
1790 | Eventually these values will be captured by @tramp{} on a system by | |
1791 | system basis and the results cached to improve performance. | |
1792 | ||
1793 | ||
1794 | @node Files directories and paths | |
1795 | @chapter How file names, directories and paths are mangled and managed. | |
1796 | ||
1797 | @menu | |
1798 | * Path deconstruction:: Breaking a path into its components. | |
1799 | @end menu | |
1800 | ||
1801 | ||
1802 | @node Path deconstruction | |
1803 | @section Breaking a path into its components. | |
1804 | ||
1805 | @tramp{} filenames are somewhat different, obviously, to ordinary path | |
1806 | names. As such, the lisp functions @code{file-name-directory} and | |
1807 | @code{file-name-nondirectory} are overridden within the @tramp{} package. | |
1808 | ||
1809 | Their replacements are reasonably simplistic in their approach. They | |
1810 | dissect the filename, call the original handler on the remote path and | |
1811 | then rebuild the @tramp{} path with the result. | |
1812 | ||
1813 | This allows the platform specific hacks in the original handlers to take | |
1814 | effect while preserving the @tramp{} path information. | |
1815 | ||
1816 | ||
1817 | @node Issues | |
1818 | @chapter Debatable Issues and What Was Decided | |
1819 | ||
1820 | @itemize @bullet | |
1821 | @item The uuencode method does not always work. | |
1822 | ||
1823 | Due to the design of @tramp{}, the encoding and decoding programs need to | |
1824 | read from stdin and write to stdout. On some systems, @code{uudecode -o | |
1825 | -} will read stdin and write the decoded file to stdout, on other | |
1826 | systems @code{uudecode -p} does the same thing. But some systems have | |
1827 | uudecode implementations which cannot do this at all---it is not | |
1828 | possible to call these uudecode implementations with suitable parameters | |
1829 | so that they write to stdout. | |
1830 | ||
1831 | Of course, this could be circumvented: the @code{begin foo 644} line | |
1832 | could be rewritten to put in some temporary file name, then | |
1833 | @code{uudecode} could be called, then the temp file could be printed and | |
1834 | deleted. | |
1835 | ||
1836 | But I have decided that this is too fragile to reliably work, so on some | |
1837 | systems you'll have to do without the uuencode methods. | |
1838 | ||
1839 | @item @tramp{} does not work on XEmacs 20. | |
1840 | ||
1841 | This is because it requires the macro @code{with-timeout} which does not | |
1842 | appear to exist in XEmacs 20. I'm somewhat reluctant to add an | |
1843 | emulation macro to @tramp{}, but if somebody who uses XEmacs 20 steps | |
1844 | forward and wishes to implement and test it, please contact me or the | |
1845 | mailing list. | |
1846 | ||
f37fc5a7 KG |
1847 | @item The @tramp{} filename syntax differs between Emacs and XEmacs. |
1848 | ||
1849 | The Emacs maintainers wish to use a unified filename syntax for | |
1850 | Ange-FTP and @tramp{} so that users don't have to learn a new | |
1851 | syntax. It is sufficient to learn some extensions to the old syntax. | |
1852 | ||
1853 | For the XEmacs maintainers, the problems caused from using a unified | |
1854 | filename syntax are greater than the gains. The XEmacs package | |
1855 | system uses EFS for downloading new packages. So, obviously, EFS has | |
1856 | to be installed from the start. If the filenames were unified, Tramp | |
1857 | would have to be installed from the start, too. | |
1858 | ||
fb7933a3 KG |
1859 | @end itemize |
1860 | ||
1861 | ||
1862 | @c End of tramp.texi - the TRAMP User Manual | |
1863 | @bye | |
1864 | ||
1865 | @c TODO | |
1866 | @c | |
1867 | @c * Say something about the .login and .profile files of the remote | |
1868 | @c shells. | |
1869 | @c * Explain how tramp.el works in principle: open a shell on a remote | |
1870 | @c host and then send commands to it. | |
83fa16cf KG |
1871 | @c * Mention that bookmarks are a cool feature to go along with Tramp. |
1872 | @c * Make terminology "inline" vs "out-of-band" consistent. | |
1873 | @c It seems that "external" is also used instead of "out-of-band". | |
fb7933a3 | 1874 |