1 \input texinfo @c -*-texinfo-*-
2 @setfilename ../../info/tramp
4 @settitle TRAMP User Manual
7 @c This is *so* much nicer :)
10 @c In the Tramp repository, the version number is auto-frobbed from
11 @c configure.ac, so you should edit that file and run
12 @c "autoconf && ./configure" to change the version number.
14 @c Additionally, flags are set with respect to the Emacs flavor; and
15 @c depending whether Tramp is packaged into (X)Emacs, or standalone.
17 @include trampver.texi
19 @c Macro for formatting a filename according to the respective syntax.
20 @c xxx and yyy are auxiliary macros in order to omit leading and
21 @c trailing whitespace. Not very elegant, but I don't know it better.
27 @macro yyy {one, two}@c
35 @macro trampfn {method, user, host, localname}@c
36 @value{prefix}@yyy{\method\,@value{postfixhop}}@yyy{\user\,@@}\host\@value{postfix}\localname\@c
40 Copyright @copyright{} 1999--2013 Free Software Foundation, Inc.
43 Permission is granted to copy, distribute and/or modify this document
44 under the terms of the GNU Free Documentation License, Version 1.3 or
45 any later version published by the Free Software Foundation; with no
46 Invariant Sections, with the Front-Cover texts being ``A GNU Manual'',
47 and with the Back-Cover Texts as in (a) below. A copy of the license
48 is included in the section entitled ``GNU Free Documentation License''.
50 (a) The FSF's Back-Cover Text is: ``You have the freedom to
51 copy and modify this GNU manual.''
55 @c Entries for @command{install-info} to use
56 @dircategory @value{emacsname} network features
58 * TRAMP: (tramp). Transparent Remote Access, Multiple Protocol
59 @value{emacsname} remote file access via rsh and rcp.
63 @title @value{tramp} version @value{trampver} User Manual
64 @author by Daniel Pittman
65 @author based on documentation by Kai Gro@ss{}johann
73 @node Top, Overview, (dir), (dir)
74 @top @value{tramp} version @value{trampver} User Manual
76 This file documents @value{tramp} version @value{trampver}, a remote file
77 editing package for @value{emacsname}.
79 @value{tramp} stands for `Transparent Remote (file) Access, Multiple
80 Protocol'. This package provides remote file editing, similar to
81 @value{ftppackagename}.
83 The difference is that @value{ftppackagename} uses FTP to transfer
84 files between the local and the remote host, whereas @value{tramp} uses a
85 combination of @command{rsh} and @command{rcp} or other work-alike
86 programs, such as @command{ssh}/@command{scp}.
88 You can find the latest version of this document on the web at
89 @uref{http://www.gnu.org/software/tramp/}.
91 @c Pointer to the other Emacs flavor is necessary only in case of
92 @c standalone installation.
94 The manual has been generated for @value{emacsname}.
96 If you want to read the info pages for @value{emacsothername}, you
97 should read in @ref{Installation} how to create them.
100 If you're using the other Emacs flavor, you should read the
101 @uref{@value{emacsotherfilename}, @value{emacsothername}} pages.
106 The latest release of @value{tramp} is available for
107 @uref{ftp://ftp.gnu.org/gnu/tramp/, download}, or you may see
108 @ref{Obtaining Tramp} for more details, including the Git server
111 @value{tramp} also has a @uref{http://savannah.gnu.org/projects/tramp/,
112 Savannah Project Page}.
115 There is a mailing list for @value{tramp}, available at
116 @email{tramp-devel@@gnu.org}, and archived at
117 @uref{http://lists.gnu.org/archive/html/tramp-devel/, the
118 @value{tramp} Mail Archive}.
120 Older archives are located at
121 @uref{http://sourceforge.net/mailarchive/forum.php?forum=tramp-devel,
122 SourceForge Mail Archive} and
123 @uref{http://www.mail-archive.com/emacs-rcp@@ls6.cs.uni-dortmund.de/,
125 @c in HTML output, there's no new paragraph.
134 * Overview:: What @value{tramp} can and cannot do.
138 * Obtaining Tramp:: How to obtain @value{tramp}.
139 * History:: History of @value{tramp}.
140 @ifset installchapter
141 * Installation:: Installing @value{tramp} with your @value{emacsname}.
143 * Configuration:: Configuring @value{tramp} for use.
144 * Usage:: An overview of the operation of @value{tramp}.
145 * Bug Reports:: Reporting Bugs and Problems.
146 * Frequently Asked Questions:: Questions and answers from the mailing list.
147 * Function Index:: @value{tramp} functions.
148 * Variable Index:: User options and variables.
149 * Concept Index:: An item for each concept.
153 * Files directories and localnames:: How file names, directories and localnames are mangled and managed.
154 * Traces and Profiles:: How to Customize Traces.
155 * Issues:: Debatable Issues and What Was Decided.
157 * GNU Free Documentation License:: The license for this documentation.
160 --- The Detailed Node Listing ---
162 @ifset installchapter
163 Installing @value{tramp} with your @value{emacsname}
165 * Installation parameters:: Parameters in order to control installation.
166 * Load paths:: How to plug-in @value{tramp} into your environment.
170 Configuring @value{tramp} for use
172 * Connection types:: Types of connections made to remote machines.
173 * Inline methods:: Inline methods.
174 * External methods:: External methods.
176 * GVFS based methods:: GVFS based external methods.
179 * Gateway methods:: Gateway methods.
181 * Default Method:: Selecting a default method.
182 * Default User:: Selecting a default user.
183 * Default Host:: Selecting a default host.
184 * Multi-hops:: Connecting to a remote host using multiple hops.
185 * Customizing Methods:: Using Non-Standard Methods.
186 * Customizing Completion:: Selecting config files for user/host name completion.
187 * Password handling:: Reusing passwords for several connections.
188 * Connection caching:: Reusing connection related information.
189 * Remote Programs:: How @value{tramp} finds and uses programs on the remote machine.
190 * Remote shell setup:: Remote shell setup hints.
191 * Android shell setup:: Android shell setup hints.
192 * Auto-save and Backup:: Auto-save and Backup.
193 * Windows setup hints:: Issues with Cygwin ssh.
197 * Filename Syntax:: @value{tramp} filename conventions.
198 * Alternative Syntax:: URL-like filename syntax.
199 * Filename completion:: Filename completion.
200 * Ad-hoc multi-hops:: Declaring multiple hops in the file name.
201 * Remote processes:: Integration with other @value{emacsname} packages.
202 * Cleanup remote connections:: Cleanup remote connections.
204 How file names, directories and localnames are mangled and managed
206 * Localname deconstruction:: Breaking a localname into its components.
208 * External packages:: Integration with external Lisp packages.
215 @chapter An overview of @value{tramp}
218 After the installation of @value{tramp} into your @value{emacsname}, you
219 will be able to access files on remote machines as though they were
220 local. Access to the remote file system for editing files, version
221 control, and @code{dired} are transparently enabled.
223 Your access to the remote machine can be with the @command{rsh},
224 @command{rlogin}, @command{telnet} programs or with any similar
225 connection method. This connection must pass @acronym{ASCII}
226 successfully to be usable but need not be 8-bit clean.
228 The package provides support for @command{ssh} connections out of the
229 box, one of the more common uses of the package. This allows
230 relatively secure access to machines, especially if @command{ftp}
233 Under Windows, @value{tramp} is integrated with the PuTTY package,
234 using the @command{plink} program.
236 The majority of activity carried out by @value{tramp} requires only that
237 the remote login is possible and is carried out at the terminal. In
238 order to access remote files @value{tramp} needs to transfer their content
239 to the local machine temporarily.
241 @value{tramp} can transfer files between the machines in a variety of ways.
242 The details are easy to select, depending on your needs and the
243 machines in question.
245 The fastest transfer methods for large files rely on a remote file
246 transfer package such as @command{rcp}, @command{scp}, @command{rsync}
247 or (under Windows) @command{pscp}.
249 If the remote copy methods are not suitable for you, @value{tramp} also
250 supports the use of encoded transfers directly through the shell.
251 This requires that the @command{mimencode} or @command{uuencode} tools
252 are available on the remote machine. These methods are generally
253 faster for small files.
255 @value{tramp} is still under active development and any problems you encounter,
256 trivial or major, should be reported to the @value{tramp} developers.
260 @subsubheading Behind the scenes
261 @cindex behind the scenes
262 @cindex details of operation
265 This section tries to explain what goes on behind the scenes when you
266 access a remote file through @value{tramp}.
268 Suppose you type @kbd{C-x C-f} and enter part of an @value{tramp} file name,
269 then hit @kbd{@key{TAB}} for completion. Suppose further that this is
270 the first time that @value{tramp} is invoked for the host in question. Here's
275 @value{tramp} discovers that it needs a connection to the host. So it
276 invokes @samp{telnet @var{host}} or @samp{rsh @var{host} -l
277 @var{user}} or a similar tool to connect to the remote host.
278 Communication with this process happens through an
279 @value{emacsname} buffer, that is, the output from the remote end
283 The remote host may prompt for a login name (for @command{telnet}).
284 The login name is given in the file name, so @value{tramp} sends the
285 login name and a newline.
288 The remote host may prompt for a password or pass phrase (for
289 @command{rsh} or for @command{telnet} after sending the login name).
290 @value{tramp} displays the prompt in the minibuffer, asking you for the
291 password or pass phrase.
293 You enter the password or pass phrase. @value{tramp} sends it to the remote
294 host, followed by a newline.
297 @value{tramp} now waits for the shell prompt or for a message that the login
300 If @value{tramp} sees neither of them after a certain period of time
301 (a minute, say), then it issues an error message saying that it
302 couldn't find the remote shell prompt and shows you what the remote
305 If @value{tramp} sees a @samp{login failed} message, it tells you so,
306 aborts the login attempt and allows you to try again.
309 Suppose that the login was successful and @value{tramp} sees the shell prompt
310 from the remote host. Now @value{tramp} invokes @command{/bin/sh} because
311 Bourne shells and C shells have different command
312 syntaxes.@footnote{Invoking @command{/bin/sh} will fail if your login
313 shell doesn't recognize @samp{exec /bin/sh} as a valid command.
314 Maybe you use the Scheme shell @command{scsh}@dots{}}
316 After the Bourne shell has come up, @value{tramp} sends a few commands to
317 ensure a good working environment. It turns off echoing, it sets the
318 shell prompt, and a few other things.
321 Now the remote shell is up and it good working order. Remember, what
322 was supposed to happen is that @value{tramp} tries to find out what files exist
323 on the remote host so that it can do filename completion.
325 So, @value{tramp} basically issues @command{cd} and @command{ls} commands and
326 also sometimes @command{echo} with globbing. Another command that is
327 often used is @command{test} to find out whether a file is writable or a
328 directory or the like. The output of each command is parsed for the
332 Suppose you are finished with filename completion, have entered @kbd{C-x
333 C-f}, a full file name and hit @kbd{@key{RET}}. Now comes the time to
334 transfer the file contents from the remote host to the local host so
335 that you can edit them.
337 See above for an explanation of how @value{tramp} transfers the file contents.
339 For inline transfers, @value{tramp} issues a command like @samp{mimencode -b
340 /path/to/remote/file}, waits until the output has accumulated in the
341 buffer that's used for communication, then decodes that output to
342 produce the file contents.
344 For external transfers, @value{tramp} issues a command like the
347 rcp user@@host:/path/to/remote/file /tmp/tramp.4711
349 It then reads the local temporary file @file{/tmp/tramp.4711} into a
350 buffer and deletes the temporary file.
353 You now edit the buffer contents, blithely unaware of what has happened
354 behind the scenes. (Unless you have read this section, that is.) When
355 you are finished, you type @kbd{C-x C-s} to save the buffer.
358 Again, @value{tramp} transfers the file contents to the remote host
359 either inline or external. This is the reverse of what happens when
363 I hope this has provided you with a basic overview of what happens
364 behind the scenes when you open a file with @value{tramp}.
368 @node Obtaining Tramp
369 @chapter Obtaining Tramp.
370 @cindex obtaining Tramp
372 @value{tramp} is freely available on the Internet and the latest
373 release may be downloaded from @uref{ftp://ftp.gnu.org/gnu/tramp/}.
374 This release includes the full documentation and code for
375 @value{tramp}, suitable for installation. But Emacs (22 or later)
376 includes @value{tramp} already, and there is a @value{tramp} package
377 for XEmacs, as well. So maybe it is easier to just use those. But if
378 you want the bleeding edge, read on@dots{}
380 For the especially brave, @value{tramp} is available from Git. The Git
381 version is the latest version of the code and may contain incomplete
382 features or new issues. Use these versions at your own risk.
384 Instructions for obtaining the latest development version of @value{tramp}
385 from Git can be found by going to the Savannah project page at the
386 following URL and then clicking on the Git link in the navigation bar
390 @uref{http://savannah.gnu.org/projects/tramp/}
393 Or follow the example session below:
396 ] @strong{cd ~/@value{emacsdir}}
397 ] @strong{git clone git://git.savannah.gnu.org/tramp.git}
401 Tramp developers use instead
404 ] @strong{git clone login@@git.sv.gnu.org:/srv/git/tramp.git}
408 You should now have a directory @file{~/@value{emacsdir}/tramp}
409 containing the latest version of @value{tramp}. You can fetch the latest
410 updates from the repository by issuing the command:
413 ] @strong{cd ~/@value{emacsdir}/tramp}
418 Once you've got updated files from the Git repository, you need to run
419 @command{autoconf} in order to get an up-to-date @file{configure}
423 ] @strong{cd ~/@value{emacsdir}/tramp}
429 @chapter History of @value{tramp}
431 @cindex development history
433 Development was started end of November 1998. The package was called
434 @file{rssh.el}, back then. It only provided one method to access a
435 file, using @command{ssh} to log in to a remote host and using
436 @command{scp} to transfer the file contents. After a while, the name
437 was changed to @file{rcp.el}, and now it's @value{tramp}. Along the way,
438 many more methods for getting a remote shell and for transferring the
439 file contents were added. Support for VC was added.
441 After that, there were added the multi-hop methods in April 2000 and
442 the unification of @value{tramp} and Ange-FTP filenames in July 2002.
443 In July 2004, multi-hop methods have been replaced by proxy hosts.
444 Running commands on remote hosts was introduced in December 2005.
446 Support of gateways exists since April 2007.
449 GVFS integration started in February 2009.
452 Remote commands on Windows hosts are available since September 2011.
454 Ad-hoc multi-hop methods (with a changed syntax) have been reenabled
455 in November 2011. In November 2012, Juergen Hoetzel's
456 @file{tramp-adb.el} has been added.
458 In December 2001, @value{tramp} has been added to the XEmacs package
459 repository. Being part of the Emacs repository happened in June 2002,
460 the first release including @value{tramp} was Emacs 22.1.
462 @value{tramp} is also a Debian GNU/Linux package since February 2001.
465 @c Installation chapter is necessary only in case of standalone
466 @c installation. Text taken from trampinst.texi.
467 @ifset installchapter
468 @include trampinst.texi
472 @chapter Configuring @value{tramp} for use
473 @cindex configuration
475 @cindex default configuration
476 @value{tramp} is (normally) fully functional when it is initially
477 installed. It is initially configured to use the @command{scp}
478 program to connect to the remote host. So in the easiest case, you
479 just type @kbd{C-x C-f} and then enter the filename
480 @file{@trampfn{, user, machine, /path/to.file}}.
482 On some hosts, there are problems with opening a connection. These are
483 related to the behavior of the remote shell. See @xref{Remote shell
484 setup}, for details on this.
486 If you do not wish to use these commands to connect to the remote
487 host, you should change the default connection and transfer method
488 that @value{tramp} uses. There are several different methods that @value{tramp}
489 can use to connect to remote machines and transfer files
490 (@pxref{Connection types}).
492 If you don't know which method is right for you, see @xref{Default
497 * Connection types:: Types of connections made to remote machines.
498 * Inline methods:: Inline methods.
499 * External methods:: External methods.
501 * GVFS based methods:: GVFS based external methods.
504 * Gateway methods:: Gateway methods.
506 * Default Method:: Selecting a default method.
507 Here we also try to help those who
508 don't have the foggiest which method
510 * Default User:: Selecting a default user.
511 * Default Host:: Selecting a default host.
512 * Multi-hops:: Connecting to a remote host using multiple hops.
513 * Customizing Methods:: Using Non-Standard Methods.
514 * Customizing Completion:: Selecting config files for user/host name completion.
515 * Password handling:: Reusing passwords for several connections.
516 * Connection caching:: Reusing connection related information.
517 * Remote Programs:: How @value{tramp} finds and uses programs on the remote machine.
518 * Remote shell setup:: Remote shell setup hints.
519 * Android shell setup:: Android shell setup hints.
520 * Auto-save and Backup:: Auto-save and Backup.
521 * Windows setup hints:: Issues with Cygwin ssh.
525 @node Connection types
526 @section Types of connections made to remote machines
527 @cindex connection types, overview
529 There are two basic types of transfer methods, each with its own
530 advantages and limitations. Both types of connection make use of a
531 remote shell access program such as @command{rsh}, @command{ssh} or
532 @command{telnet} to connect to the remote machine.
534 This connection is used to perform many of the operations that @value{tramp}
535 requires to make the remote file system transparently accessible from
536 the local machine. It is only when visiting files that the methods
539 @cindex inline methods
540 @cindex external methods
541 @cindex methods, inline
542 @cindex methods, external
543 Loading or saving a remote file requires that the content of the file
544 be transferred between the two machines. The content of the file can
545 be transferred using one of two methods: the @dfn{inline method} over
546 the same connection used to log in to the remote machine, or the
547 @dfn{external method} through another connection using a remote copy
548 program such as @command{rcp}, @command{scp} or @command{rsync}.
550 The performance of the external methods is generally better than that
551 of the inline methods, at least for large files. This is caused by
552 the need to encode and decode the data when transferring inline.
554 The one exception to this rule are the @command{scp} based transfer
555 methods. While these methods do see better performance when actually
556 transferring files, the overhead of the cryptographic negotiation at
557 startup may drown out the improvement in file transfer times.
559 External methods should be configured such a way that they don't
560 require a password (with @command{ssh-agent}, or such alike). Modern
561 @command{scp} implementations offer options to reuse existing
562 @command{ssh} connections, which will be enabled by default if
563 available. If it isn't possible, you should consider @ref{Password
564 handling}, otherwise you will be prompted for a password every copy
569 @section Inline methods
570 @cindex inline methods
571 @cindex methods, inline
573 The inline methods in @value{tramp} are quite powerful and can work in
574 situations where you cannot use an external transfer program to connect.
575 Inline methods are the only methods that work when connecting to the
576 remote machine via telnet. (There are also strange inline methods which
577 allow you to transfer files between @emph{user identities} rather than
580 These methods depend on the existence of a suitable encoding and
581 decoding command on remote machine. Locally, @value{tramp} may be able to
582 use features of @value{emacsname} to decode and encode the files or
583 it may require access to external commands to perform that task.
587 @cindex base-64 encoding
588 @value{tramp} checks the availability and usability of commands like
589 @command{mimencode} (part of the @command{metamail} package) or
590 @command{uuencode} on the remote host. The first reliable command
591 will be used. The search path can be customized, see @ref{Remote
594 If both commands aren't available on the remote host, @value{tramp}
595 transfers a small piece of Perl code to the remote host, and tries to
596 apply it for encoding and decoding.
598 The variable @var{tramp-inline-compress-start-size} controls, whether
599 a file shall be compressed before encoding. This could increase
600 transfer speed for large text files.
608 Connect to the remote host with @command{rsh}. Due to the unsecure
609 connection it is recommended for very local host topology only.
611 On operating systems which provide the command @command{remsh} instead
612 of @command{rsh}, you can use the method @option{remsh}. This is true
613 for HP-UX or Cray UNICOS, for example.
620 Connect to the remote host with @command{ssh}. This is identical to
621 the previous option except that the @command{ssh} package is used,
622 making the connection more secure.
624 There are also two variants, @option{ssh1} and @option{ssh2}, that
625 call @samp{ssh -1} and @samp{ssh -2}, respectively. This way, you can
626 explicitly select whether you want to use the SSH protocol version 1
627 or 2 to connect to the remote host. (You can also specify in
628 @file{~/.ssh/config}, the SSH configuration file, which protocol
629 should be used, and use the regular @option{ssh} method.)
631 All the methods based on @command{ssh} have an additional feature: you
632 can specify a host name which looks like @file{host#42} (the real host
633 name, then a hash sign, then a port number). This means to connect to
634 the given host but to also pass @code{-p 42} as arguments to the
635 @command{ssh} command.
638 @item @option{telnet}
639 @cindex method telnet
640 @cindex telnet method
642 Connect to the remote host with @command{telnet}. This is as unsecure
643 as the @option{rsh} method.
650 This method does not connect to a remote host at all, rather it uses
651 the @command{su} program to allow you to edit files as another user.
652 That means, the specified host name in the file name must be either
653 @samp{localhost} or the host name as returned by the function
654 @command{(system-name)}. For an exception of this rule see
662 This is similar to the @option{su} method, but it uses @command{sudo}
663 rather than @command{su} to become a different user.
665 Note that @command{sudo} must be configured to allow you to start a
666 shell as the user. It would be nice if it was sufficient if
667 @command{ls} and @command{mimencode} were allowed, but that is not
668 easy to implement, so I haven't got around to it, yet.
675 As you would expect, this is similar to @option{ssh}, only a little
676 different. Whereas @option{ssh} opens a normal interactive shell on
677 the remote host, this option uses @samp{ssh -t -t @var{host} -l
678 @var{user} /bin/sh} to open a connection. This is useful for users
679 where the normal login shell is set up to ask them a number of
680 questions when logging in. This procedure avoids these questions, and
681 just gives @value{tramp} a more-or-less `standard' login shell to work
684 Note that this procedure does not eliminate questions asked by
685 @command{ssh} itself. For example, @command{ssh} might ask ``Are you
686 sure you want to continue connecting?'' if the host key of the remote
687 host is not known. @value{tramp} does not know how to deal with such a
688 question (yet), therefore you will need to make sure that you can log
689 in without such questions.
691 This is also useful for Windows users where @command{ssh}, when
692 invoked from an @value{emacsname} buffer, tells them that it is not
693 allocating a pseudo tty. When this happens, the login shell is wont
694 to not print any shell prompt, which confuses @value{tramp} mightily.
696 This supports the @samp{-p} argument.
699 @item @option{krlogin}
700 @cindex method krlogin
701 @cindex krlogin method
702 @cindex Kerberos (with krlogin method)
704 This method is also similar to @option{ssh}. It only uses the
705 @command{krlogin -x} command to log in to the remote host.
711 @cindex Kerberos (with ksu method)
713 This is another method from the Kerberos suite. It behaves like @option{su}.
720 This method is mostly interesting for Windows users using the PuTTY
721 implementation of SSH@. It uses @samp{plink -ssh} to log in to the
724 This supports the @samp{-P} argument.
726 Additionally, the methods @option{plink1} and @option{plink2} are
727 provided, which call @samp{plink -1 -ssh} or @samp{plink -2 -ssh} in
728 order to use SSH protocol version 1 or 2 explicitly.
730 CCC: Do we have to connect to the remote host once from the command
731 line to accept the SSH key? Maybe this can be made automatic?
733 CCC: Say something about the first shell command failing. This might
734 be due to a wrong setting of @code{tramp-rsh-end-of-line}.
737 @item @option{plinkx}
738 @cindex method plinkx
739 @cindex plinkx method
741 Another method using PuTTY on Windows. Instead of host names, it
742 expects PuTTY session names, calling @samp{plink -load @var{session}
743 -t"}. User names are relevant only in case the corresponding session
744 hasn't defined a user name. Different port numbers must be defined in
750 @node External methods
751 @section External methods
752 @cindex methods, external
753 @cindex external methods
755 The external methods operate through multiple channels, using the
756 remote shell connection for many actions while delegating file
757 transfers to an external transfer utility.
759 This saves the overhead of encoding and decoding that multiplexing the
760 transfer through the one connection has with the inline methods.
762 Since external methods need their own overhead opening a new channel,
763 all files which are smaller than @var{tramp-copy-size-limit} are still
764 transferred with the corresponding inline method. It should provide a
765 fair trade-off between both approaches.
768 @item @option{rcp}---@command{rsh} and @command{rcp}
771 @cindex rcp (with rcp method)
772 @cindex rsh (with rcp method)
774 This method uses the @command{rsh} and @command{rcp} commands to connect
775 to the remote machine and transfer files. This is probably the fastest
776 connection method available.
778 The alternative method @option{remcp} uses the @command{remsh} and
779 @command{rcp} commands. It should be applied on machines where
780 @command{remsh} is used instead of @command{rsh}.
783 @item @option{scp}---@command{ssh} and @command{scp}
786 @cindex scp (with scp method)
787 @cindex ssh (with scp method)
789 Using @command{ssh} to connect to the remote host and @command{scp} to
790 transfer files between the machines is the best method for securely
791 connecting to a remote machine and accessing files.
793 The performance of this option is also quite good. It may be slower than
794 the inline methods when you often open and close small files however.
795 The cost of the cryptographic handshake at the start of an @command{scp}
796 session can begin to absorb the advantage that the lack of encoding and
799 There are also two variants, @option{scp1} and @option{scp2}, that
800 call @samp{ssh -1} and @samp{ssh -2}, respectively. This way, you can
801 explicitly select whether you want to use the SSH protocol version 1
802 or 2 to connect to the remote host. (You can also specify in
803 @file{~/.ssh/config}, the SSH configuration file, which protocol
804 should be used, and use the regular @option{scp} method.)
806 All the @command{ssh} based methods support the @samp{-p} feature
807 where you can specify a port number to connect to in the host name.
808 For example, the host name @file{host#42} tells @value{tramp} to
809 specify @samp{-p 42} in the argument list for @command{ssh}, and to
810 specify @samp{-P 42} in the argument list for @command{scp}.
813 @item @option{sftp}---@command{ssh} and @command{sftp}
816 @cindex sftp (with sftp method)
817 @cindex ssh (with sftp method)
819 That is mostly the same method as @option{scp}, but using
820 @command{sftp} as transfer command. So the same remarks are valid.
822 This command does not work like @value{ftppackagename}, where
823 @command{ftp} is called interactively, and all commands are send from
824 within this session. Instead of, @command{ssh} is used for login.
826 This method supports the @samp{-p} argument.
829 @item @option{rsync}---@command{ssh} and @command{rsync}
832 @cindex rsync (with rsync method)
833 @cindex ssh (with rsync method)
835 Using the @command{ssh} command to connect securely to the remote
836 machine and the @command{rsync} command to transfer files is almost
837 identical to the @option{scp} method.
839 While @command{rsync} performs much better than @command{scp} when
840 transferring files that exist on both hosts, this advantage is lost if
841 the file exists only on one side of the connection. A file can exists
842 on both the remote and local host, when you copy a file from/to a
843 remote host. When you just open a file from the remote host (or write
844 a file there), a temporary file on the local side is kept as long as
845 the corresponding buffer, visiting this file, is alive.
847 This method supports the @samp{-p} argument.
850 @item @option{scpx}---@command{ssh} and @command{scp}
853 @cindex scp (with scpx method)
854 @cindex ssh (with scpx method)
856 As you would expect, this is similar to @option{scp}, only a little
857 different. Whereas @option{scp} opens a normal interactive shell on
858 the remote host, this option uses @samp{ssh -t -t @var{host} -l
859 @var{user} /bin/sh} to open a connection. This is useful for users
860 where the normal login shell is set up to ask them a number of
861 questions when logging in. This procedure avoids these questions, and
862 just gives @value{tramp} a more-or-less `standard' login shell to work
865 This is also useful for Windows users where @command{ssh}, when
866 invoked from an @value{emacsname} buffer, tells them that it is not
867 allocating a pseudo tty. When this happens, the login shell is wont
868 to not print any shell prompt, which confuses @value{tramp} mightily.
870 This method supports the @samp{-p} argument.
873 @item @option{pscp}---@command{plink} and @command{pscp}
876 @cindex pscp (with pscp method)
877 @cindex plink (with pscp method)
878 @cindex PuTTY (with pscp method)
880 This method is similar to @option{scp}, but it uses the
881 @command{plink} command to connect to the remote host, and it uses
882 @command{pscp} for transferring the files. These programs are part
883 of PuTTY, an SSH implementation for Windows.
885 This method supports the @samp{-P} argument.
888 @item @option{psftp}---@command{plink} and @command{psftp}
891 @cindex psftp (with psftp method)
892 @cindex plink (with psftp method)
893 @cindex PuTTY (with psftp method)
895 As you would expect, this method is similar to @option{sftp}, but it
896 uses the @command{plink} command to connect to the remote host, and it
897 uses @command{psftp} for transferring the files. These programs are
898 part of PuTTY, an SSH implementation for Windows.
900 This method supports the @samp{-P} argument.
903 @item @option{fcp}---@command{fsh} and @command{fcp}
906 @cindex fsh (with fcp method)
907 @cindex fcp (with fcp method)
909 This method is similar to @option{scp}, but it uses the @command{fsh}
910 command to connect to the remote host, and it uses @command{fcp} for
911 transferring the files. @command{fsh/fcp} are a front-end for
912 @command{ssh} which allow for reusing the same @command{ssh} session
913 for submitting several commands. This avoids the startup overhead of
914 @command{scp} (which has to establish a secure connection whenever it
915 is called). Note, however, that you can also use one of the inline
916 methods to achieve a similar effect.
918 This method uses the command @samp{fsh @var{host} -l @var{user}
919 /bin/sh -i} to establish the connection, it does not work to just say
920 @command{fsh @var{host} -l @var{user}}.
925 There is no inline method using @command{fsh} as the multiplexing
926 provided by the program is not very useful in our context. @value{tramp}
927 opens just one connection to the remote host and then keeps it open,
935 This is not a native @value{tramp} method. Instead, it forwards all
936 requests to @value{ftppackagename}.
938 This works only for unified filenames, see @ref{Issues}.
942 @item @option{smb}---@command{smbclient}
946 This is another not native @value{tramp} method. It uses the
947 @command{smbclient} command on different Unices in order to connect to
948 an SMB server. An SMB server might be a Samba (or CIFS) server on
949 another UNIX host or, more interesting, a host running MS Windows. So
950 far, it is tested against MS Windows NT, MS Windows 2000, MS Windows
951 XP, MS Windows Vista, and MS Windows 7.
953 The first directory in the localname must be a share name on the remote
954 host. Remember that the @code{$} character, in which default shares
955 usually end, must be written @code{$$} due to environment variable
956 substitution in file names. If no share name is given (i.e., remote
957 directory @code{/}), all available shares are listed.
959 Since authorization is done on share level, you will always be
960 prompted for a password if you access another share on the same host.
961 This can be suppressed by @ref{Password handling}.
963 For authorization, MS Windows uses both a user name and a domain name.
964 Because of this, the @value{tramp} syntax has been extended: you can
965 specify a user name which looks like @code{user%domain} (the real user
966 name, then a percent sign, then the domain name). So, to connect to
967 the machine @code{melancholia} as user @code{daniel} of the domain
968 @code{BIZARRE}, and edit @file{.emacs} in the home directory (share
969 @code{daniel$}) I would specify the filename @file{@trampfn{smb,
970 daniel%BIZARRE, melancholia, /daniel$$/.emacs}}.
972 Depending on the Windows domain configuration, a Windows user might be
973 considered as domain user per default. In order to connect as local
974 user, the WINS name of that machine must be given as domain name.
975 Usually, it is the machine name in capital letters. In the example
976 above, the local user @code{daniel} would be specified as
977 @file{@trampfn{smb, daniel%MELANCHOLIA, melancholia, /daniel$$/.emacs}}.
979 The domain name as well as the user name are optional. If no user
980 name is specified at all, the anonymous user (without password
981 prompting) is assumed. This is different from all other @value{tramp}
982 methods, where in such a case the local user name is taken.
984 The @option{smb} method supports the @samp{-p} argument.
986 @strong{Please note:} If @value{emacsname} runs locally under MS
987 Windows, this method isn't available. Instead, you can use UNC
988 file names like @file{//melancholia/daniel$$/.emacs}. The only
989 disadvantage is that there's no possibility to specify another user
997 This special method uses the Android Debug Bridge for connecting
998 Android devices. The Android Debug Bridge, part of the Android SDK,
999 must be installed locally. The variable @var{tramp-adb-sdk-dir} must
1000 be set to its installation directory.
1006 @node GVFS based methods
1007 @section GVFS based external methods
1008 @cindex methods, gvfs
1009 @cindex gvfs based methods
1012 The connection methods described in this section are based on GVFS
1013 @uref{http://en.wikipedia.org/wiki/GVFS}. Via GVFS, the remote
1014 filesystem is mounted locally through FUSE@. @value{tramp} uses
1015 this local mounted directory internally.
1017 The communication with GVFS is implemented via D-Bus messages.
1018 Therefore, your @value{emacsname} must have D-Bus integration,
1019 @pxref{Top, , D-Bus, dbus}.
1028 This method provides access to WebDAV files and directories. There
1029 exists also the external method @option{davs}, which uses SSL
1030 encryption for the access.
1032 Both methods support the port number specification as discussed above.
1039 OBEX is an FTP-like access protocol for simple devices, like cell
1040 phones. For the time being, @value{tramp} only supports OBEX over Bluetooth.
1043 @item @option{synce}
1044 @cindex method synce
1045 @cindex synce method
1047 The @option{synce} method allows communication with Windows Mobile
1048 devices. Beside GVFS for mounting remote files and directories via
1049 FUSE, it also needs the SYNCE-GVFS plugin.
1053 @defopt tramp-gvfs-methods
1054 This customer option, a list, defines the external methods which
1055 shall be used with GVFS@. Per default, these are @option{dav},
1056 @option{davs}, @option{obex} and @option{synce}. Other possible
1057 values are @option{ftp}, @option{sftp} and @option{smb}.
1063 @node Gateway methods
1064 @section Gateway methods
1065 @cindex methods, gateway
1066 @cindex gateway methods
1068 Gateway methods are not methods to access a remote host directly.
1069 These methods are intended to pass firewalls or proxy servers.
1070 Therefore, they can be used for proxy host declarations
1071 (@pxref{Multi-hops}) only.
1073 A gateway method must always come along with a method which supports
1074 port setting. This is because @value{tramp} targets the accompanied
1075 method to @file{localhost#random_port}, from where the firewall or
1076 proxy server is accessed.
1078 Gateway methods support user name and password declarations. These
1079 are used to authenticate towards the corresponding firewall or proxy
1080 server. They can be passed only if your friendly administrator has
1081 granted your access.
1084 @item @option{tunnel}
1085 @cindex method tunnel
1086 @cindex tunnel method
1088 This method implements an HTTP tunnel via the @command{CONNECT}
1089 command (see RFC 2616, 2817). Any HTTP 1.1 compliant (proxy) server
1090 shall support this command.
1092 As authentication method, only @option{Basic Authentication} (see RFC
1093 2617) is implemented so far. If no port number is given in the
1094 declaration, port @option{8080} is used for the proxy server.
1097 @item @option{socks}
1098 @cindex method socks
1099 @cindex socks method
1101 The @command{socks} method provides access to SOCKSv5 servers (see
1102 RFC 1928). @option{Username/Password Authentication} according to RFC
1105 The default port number of the socks server is @option{1080}, if not
1106 specified otherwise.
1112 @node Default Method
1113 @section Selecting a default method
1114 @cindex default method
1116 @vindex tramp-default-method
1117 When you select an appropriate transfer method for your typical usage
1118 you should set the variable @code{tramp-default-method} to reflect that
1119 choice. This variable controls which method will be used when a method
1120 is not specified in the @value{tramp} file name. For example:
1123 (setq tramp-default-method "ssh")
1126 @vindex tramp-default-method-alist
1127 You can also specify different methods for certain user/host
1128 combinations, via the variable @code{tramp-default-method-alist}. For
1129 example, the following two lines specify to use the @option{ssh}
1130 method for all user names matching @samp{john} and the @option{rsync}
1131 method for all host names matching @samp{lily}. The third line
1132 specifies to use the @option{su} method for the user @samp{root} on
1133 the machine @samp{localhost}.
1136 (add-to-list 'tramp-default-method-alist '("" "john" "ssh"))
1137 (add-to-list 'tramp-default-method-alist '("lily" "" "rsync"))
1138 (add-to-list 'tramp-default-method-alist
1139 '("\\`localhost\\'" "\\`root\\'" "su"))
1143 See the documentation for the variable
1144 @code{tramp-default-method-alist} for more details.
1146 External methods are normally preferable to inline methods, giving
1149 @xref{Inline methods}.
1150 @xref{External methods}.
1152 Another consideration with the selection of transfer methods is the
1153 environment you will use them in and, especially when used over the
1154 Internet, the security implications of your preferred method.
1156 The @option{rsh} and @option{telnet} methods send your password as
1157 plain text as you log in to the remote machine, as well as
1158 transferring the files in such a way that the content can easily be
1159 read from other machines.
1161 If you need to connect to remote systems that are accessible from the
1162 Internet, you should give serious thought to using @option{ssh} based
1163 methods to connect. These provide a much higher level of security,
1164 making it a non-trivial exercise for someone to obtain your password
1165 or read the content of the files you are editing.
1168 @subsection Which method is the right one for me?
1169 @cindex choosing the right method
1171 Given all of the above, you are probably thinking that this is all fine
1172 and good, but it's not helping you to choose a method! Right you are.
1173 As a developer, we don't want to boss our users around but give them
1174 maximum freedom instead. However, the reality is that some users would
1175 like to have some guidance, so here I'll try to give you this guidance
1176 without bossing you around. You tell me whether it works @dots{}
1178 My suggestion is to use an inline method. For large files, external
1179 methods might be more efficient, but I guess that most people will
1180 want to edit mostly small files. And if you access large text files,
1181 compression (driven by @var{tramp-inline-compress-start-size}) shall
1182 still result in good performance.
1184 I guess that these days, most people can access a remote machine by
1185 using @command{ssh}. So I suggest that you use the @option{ssh}
1186 method. So, type @kbd{C-x C-f @trampfn{ssh, root, otherhost,
1187 /etc/motd} @key{RET}} to edit the @file{/etc/motd} file on the other
1190 If you can't use @option{ssh} to log in to the remote host, then
1191 select a method that uses a program that works. For instance, Windows
1192 users might like the @option{plink} method which uses the PuTTY
1193 implementation of @command{ssh}. Or you use Kerberos and thus like
1196 For the special case of editing files on the local host as another
1197 user, see the @option{su} or @option{sudo} methods. They offer
1198 shortened syntax for the @samp{root} account, like
1199 @file{@trampfn{su, , , /etc/motd}}.
1201 People who edit large files may want to consider @option{scp} instead
1202 of @option{ssh}, or @option{pscp} instead of @option{plink}. These
1203 external methods are faster than inline methods for large files.
1204 Note, however, that external methods suffer from some limitations.
1205 Please try first whether you really get a noticeable speed advantage
1206 from using an external method! Maybe even for large files, inline
1207 methods are fast enough.
1211 @section Selecting a default user
1212 @cindex default user
1214 The user part of a @value{tramp} file name can be omitted. Usually,
1215 it is replaced by the user name you are logged in. Often, this is not
1216 what you want. A typical use of @value{tramp} might be to edit some
1217 files with root permissions on the local host. This case, you should
1218 set the variable @code{tramp-default-user} to reflect that choice.
1222 (setq tramp-default-user "root")
1225 @code{tramp-default-user} is regarded as obsolete, and will be removed
1228 @vindex tramp-default-user-alist
1229 You can also specify different users for certain method/host
1230 combinations, via the variable @code{tramp-default-user-alist}. For
1231 example, if you always have to use the user @samp{john} in the domain
1232 @samp{somewhere.else}, you can specify the following:
1235 (add-to-list 'tramp-default-user-alist
1236 '("ssh" ".*\\.somewhere\\.else\\'" "john"))
1240 See the documentation for the variable @code{tramp-default-user-alist}
1243 One trap to fall in must be known. If @value{tramp} finds a default
1244 user, this user will be passed always to the connection command as
1245 parameter (for example @command{ssh here.somewhere.else -l john}. If
1246 you have specified another user for your command in its configuration
1247 files, @value{tramp} cannot know it, and the remote access will fail.
1248 If you have specified in the given example in @file{~/.ssh/config} the
1252 Host here.somewhere.else
1257 than you must discard selecting a default user by @value{tramp}. This
1258 will be done by setting it to @code{nil} (or @samp{lily}, likewise):
1261 (add-to-list 'tramp-default-user-alist
1262 '("ssh" "\\`here\\.somewhere\\.else\\'" nil))
1265 The last entry in @code{tramp-default-user-alist} could be your
1266 default user you'll apply predominantly. You shall @emph{append} it
1267 to that list at the end:
1270 (add-to-list 'tramp-default-user-alist '(nil nil "jonas") t)
1275 @section Selecting a default host
1276 @cindex default host
1278 @vindex tramp-default-host
1279 Finally, it is even possible to omit the host name part of a
1280 @value{tramp} file name. This case, the value of the variable
1281 @code{tramp-default-host} is used. Per default, it is initialized
1282 with the host name your local @value{emacsname} is running.
1284 If you, for example, use @value{tramp} mainly to contact the host
1285 @samp{target} as user @samp{john}, you can specify:
1288 (setq tramp-default-user "john"
1289 tramp-default-host "target")
1292 Then the simple file name @samp{@trampfn{ssh, , ,}} will connect you
1293 to John's home directory on target.
1295 Note, however, that the most simplification @samp{/::} won't work,
1296 because @samp{/:} is the prefix for quoted file names.
1299 @vindex tramp-default-host-alist
1300 Like with methods and users, you can also specify different default
1301 hosts for certain method/user combinations via the variable
1302 @code{tramp-default-host-alist}. Usually, this isn't necessary,
1303 because @code{tramp-default-host} should be sufficient. For some
1304 methods, like @option{adb}, that default value must be overwritten,
1305 which is already the initial value of @code{tramp-default-host-alist}.
1308 See the documentation for the variable @code{tramp-default-host-alist}
1313 @section Connecting to a remote host using multiple hops
1317 Sometimes, the methods described before are not sufficient.
1318 Sometimes, it is not possible to connect to a remote host using a
1319 simple command. For example, if you are in a secured network, you
1320 might have to log in to a bastion host first before you can connect to
1321 the outside world. Of course, the target host may also require a
1324 @vindex tramp-default-proxies-alist
1325 @defopt tramp-default-proxies-alist
1326 In order to specify multiple hops, it is possible to define a proxy
1327 host to pass through, via the variable
1328 @code{tramp-default-proxies-alist}. This variable keeps a list of
1329 triples (@var{host} @var{user} @var{proxy}).
1331 The first matching item specifies the proxy host to be passed for a
1332 file name located on a remote target matching @var{user}@@@var{host}.
1333 @var{host} and @var{user} are regular expressions or @code{nil}, which
1334 is interpreted as a regular expression which always matches.
1336 @var{proxy} must be a Tramp filename which localname part is ignored.
1337 Method and user name on @var{proxy} are optional, which is interpreted
1338 with the default values.
1340 The method must be an inline or gateway method (@pxref{Inline
1341 methods}, @pxref{Gateway methods}).
1344 The method must be an inline method (@pxref{Inline methods}).
1346 If @var{proxy} is @code{nil}, no additional hop is required reaching
1347 @var{user}@@@var{host}.
1349 If you, for example, must pass the host @samp{bastion.your.domain} as
1350 user @samp{bird} for any remote host which is not located in your local
1354 (add-to-list 'tramp-default-proxies-alist
1355 '("\\." nil "@trampfn{ssh, bird, bastion.your.domain,}"))
1356 (add-to-list 'tramp-default-proxies-alist
1357 '("\\.your\\.domain\\'" nil nil))
1360 Please note the order of the code. @code{add-to-list} adds elements at the
1361 beginning of a list. Therefore, most relevant rules must be added last.
1363 Proxy hosts can be cascaded. If there is another host called
1364 @samp{jump.your.domain}, which is the only one in your local domain who
1365 is allowed connecting @samp{bastion.your.domain}, you can add another
1369 (add-to-list 'tramp-default-proxies-alist
1370 '("\\`bastion\\.your\\.domain\\'"
1372 "@trampfn{ssh, , jump.your.domain,}"))
1375 @var{proxy} can contain the patterns @code{%h} or @code{%u}. These
1376 patterns are replaced by the strings matching @var{host} or
1377 @var{user}, respectively.
1379 If you, for example, wants to work as @samp{root} on hosts in the
1380 domain @samp{your.domain}, but login as @samp{root} is disabled for
1381 non-local access, you might add the following rule:
1384 (add-to-list 'tramp-default-proxies-alist
1385 '("\\.your\\.domain\\'" "\\`root\\'" "@trampfn{ssh, , %h,}"))
1388 Opening @file{@trampfn{sudo, , randomhost.your.domain,}} would connect
1389 first @samp{randomhost.your.domain} via @code{ssh} under your account
1390 name, and perform @code{sudo -u root} on that host afterwards. It is
1391 important to know that the given method is applied on the host which
1392 has been reached so far. @code{sudo -u root}, applied on your local
1393 host, wouldn't be useful here.
1395 @var{host}, @var{user} and @var{proxy} can also be Lisp forms. These
1396 forms are evaluated, and must return a string, or @code{nil}. The
1397 previous example could be generalized then: For all hosts except my
1398 local one connect via @command{ssh} first, and apply @command{sudo -u
1402 (add-to-list 'tramp-default-proxies-alist
1403 '(nil "\\`root\\'" "@trampfn{ssh, , %h,}"))
1404 (add-to-list 'tramp-default-proxies-alist
1405 '((regexp-quote (system-name)) nil nil))
1408 This is the recommended configuration to work as @samp{root} on remote
1412 Finally, @code{tramp-default-proxies-alist} can be used to pass
1413 firewalls or proxy servers. Imagine your local network has a host
1414 @samp{proxy.your.domain} which is used on port 3128 as HTTP proxy to
1415 the outer world. Your friendly administrator has granted you access
1416 under your user name to @samp{host.other.domain} on that proxy
1417 server.@footnote{HTTP tunnels are intended for secure SSL/TLS
1418 communication. Therefore, many proxy server restrict the tunnels to
1419 related target ports. You might need to run your ssh server on your
1420 target host @samp{host.other.domain} on such a port, like 443 (https).
1421 See @uref{http://savannah.gnu.org/maintenance/CvsFromBehindFirewall}
1422 for discussion of ethical issues.} You would need to add the
1426 (add-to-list 'tramp-default-proxies-alist
1427 '("\\`host\\.other\\.domain\\'" nil
1428 "@trampfn{tunnel, , proxy.your.domain#3128,}"))
1431 Gateway methods can be declared as first hop only in a multiple hop
1436 Hops to be passed tend to be restricted firewalls and alike.
1437 Sometimes they offer limited features only, like running @command{rbash}
1438 (restricted bash). This must be told to @value{tramp}.
1440 @vindex tramp-restricted-shell-hosts-alist
1441 @defopt tramp-restricted-shell-hosts-alist
1442 This variable keeps a list of regular expressions, which denote hosts
1443 running a registered shell like "rbash". Those hosts can be used as
1446 If the bastion host from the example above runs a restricted shell,
1450 (add-to-list 'tramp-restricted-shell-hosts-alist
1451 "\\`bastion\\.your\\.domain\\'")
1456 @node Customizing Methods
1457 @section Using Non-Standard Methods
1458 @cindex customizing methods
1459 @cindex using non-standard methods
1460 @cindex create your own methods
1462 There is a variable @code{tramp-methods} which you can change if the
1463 predefined methods don't seem right.
1465 For the time being, I'll refer you to the Lisp documentation of that
1466 variable, accessible with @kbd{C-h v tramp-methods @key{RET}}.
1469 @node Customizing Completion
1470 @section Selecting config files for user/host name completion
1471 @cindex customizing completion
1472 @cindex selecting config files
1473 @vindex tramp-completion-function-alist
1475 The variable @code{tramp-completion-function-alist} is intended to
1476 customize which files are taken into account for user and host name
1477 completion (@pxref{Filename completion}). For every method, it keeps
1478 a set of configuration files, accompanied by a Lisp function able to
1479 parse that file. Entries in @code{tramp-completion-function-alist}
1480 have the form (@var{method} @var{pair1} @var{pair2} ...).
1482 Each @var{pair} is composed of (@var{function} @var{file}).
1483 @var{function} is responsible to extract user names and host names
1484 from @var{file} for completion. There are two functions which access
1487 @defun tramp-get-completion-function method
1488 This function returns the list of completion functions for @var{method}.
1492 (tramp-get-completion-function "rsh")
1494 @result{} ((tramp-parse-rhosts "/etc/hosts.equiv")
1495 (tramp-parse-rhosts "~/.rhosts"))
1499 @defun tramp-set-completion-function method function-list
1500 This function sets @var{function-list} as list of completion functions
1505 (tramp-set-completion-function "ssh"
1506 '((tramp-parse-sconfig "/etc/ssh_config")
1507 (tramp-parse-sconfig "~/.ssh/config")))
1509 @result{} ((tramp-parse-sconfig "/etc/ssh_config")
1510 (tramp-parse-sconfig "~/.ssh/config"))
1514 The following predefined functions parsing configuration files exist:
1517 @item @code{tramp-parse-rhosts}
1518 @findex tramp-parse-rhosts
1520 This function parses files which are syntactical equivalent to
1521 @file{~/.rhosts}. It returns both host names and user names, if
1524 @item @code{tramp-parse-shosts}
1525 @findex tramp-parse-shosts
1527 This function parses files which are syntactical equivalent to
1528 @file{~/.ssh/known_hosts}. Since there are no user names specified
1529 in such files, it can return host names only.
1531 @item @code{tramp-parse-sconfig}
1532 @findex tramp-parse-shosts
1534 This function returns the host nicknames defined by @code{Host} entries
1535 in @file{~/.ssh/config} style files.
1537 @item @code{tramp-parse-shostkeys}
1538 @findex tramp-parse-shostkeys
1540 SSH2 parsing of directories @file{/etc/ssh2/hostkeys/*} and
1541 @file{~/ssh2/hostkeys/*}. Hosts are coded in file names
1542 @file{hostkey_@var{portnumber}_@var{host-name}.pub}. User names
1543 are always @code{nil}.
1545 @item @code{tramp-parse-sknownhosts}
1546 @findex tramp-parse-shostkeys
1548 Another SSH2 style parsing of directories like
1549 @file{/etc/ssh2/knownhosts/*} and @file{~/ssh2/knownhosts/*}. This
1550 case, hosts names are coded in file names
1551 @file{@var{host-name}.@var{algorithm}.pub}. User names are always @code{nil}.
1553 @item @code{tramp-parse-hosts}
1554 @findex tramp-parse-hosts
1556 A function dedicated to @file{/etc/hosts} style files. It returns
1559 @item @code{tramp-parse-passwd}
1560 @findex tramp-parse-passwd
1562 A function which parses @file{/etc/passwd} like files. Obviously, it
1563 can return user names only.
1565 @item @code{tramp-parse-netrc}
1566 @findex tramp-parse-netrc
1568 Finally, a function which parses @file{~/.netrc} like files. This
1569 includes also @file{~/.authinfo}-style files.
1573 If you want to keep your own data in a file, with your own structure,
1574 you might provide such a function as well. This function must meet
1575 the following conventions:
1577 @defun my-tramp-parse file
1578 @var{file} must be either a file name on your host, or @code{nil}.
1579 The function must return a list of (@var{user} @var{host}), which are
1580 taken as candidates for user and host name completion.
1584 (my-tramp-parse "~/.my-tramp-hosts")
1586 @result{} ((nil "toto") ("daniel" "melancholia"))
1591 @node Password handling
1592 @section Reusing passwords for several connections
1595 Sometimes it is necessary to connect to the same remote host several
1596 times. Reentering passwords again and again would be annoying, when
1597 the chosen method does not support access without password prompt
1598 through own configuration.
1600 The best recommendation is to use the method's own mechanism for
1601 password handling. Consider @command{ssh-agent} for @option{ssh}-like
1602 methods, or @command{pageant} for @option{plink}-like methods.
1604 However, if you cannot apply such native password handling,
1605 @value{tramp} offers alternatives.
1608 @anchor{Using an authentication file}
1609 @subsection Using an authentication file
1611 @vindex auth-sources
1612 The package @file{auth-source.el}, originally developed in No Gnus,
1613 offers the possibility to read passwords from a file, like FTP does it
1614 from @file{~/.netrc}. The default authentication file is
1615 @file{~/.authinfo.gpg}, this can be changed via the variable
1616 @code{auth-sources}.
1619 A typical entry in the authentication file would be
1622 machine melancholia port scp login daniel password geheim
1625 The port can be any @value{tramp} method (@pxref{Inline methods},
1626 @pxref{External methods}), to match only this method. When you omit
1627 the port, you match all @value{tramp} methods.
1629 In case of problems, setting @code{auth-source-debug} to @code{t}
1630 gives useful debug messages.
1633 @anchor{Caching passwords}
1634 @subsection Caching passwords
1636 If there is no authentication file, @value{tramp} caches the passwords
1637 entered by you. They will be reused next time if a connection needs
1638 them for the same user name and host name, independently of the
1641 @vindex password-cache-expiry
1642 Passwords are not saved permanently, that means the password caching
1643 is limited to the lifetime of your @value{emacsname} session. You
1644 can influence the lifetime of password caching by customizing the
1645 variable @code{password-cache-expiry}. The value is the number of
1646 seconds how long passwords are cached. Setting it to @code{nil}
1647 disables the expiration.
1649 @vindex password-cache
1650 If you don't like this feature for security reasons, password caching
1651 can be disabled totally by customizing the variable
1652 @code{password-cache} (setting it to @code{nil}).
1654 Implementation Note: password caching is based on the package
1655 @file{password-cache.el}. For the time being, it is activated only
1656 when this package is seen in the @code{load-path} while loading
1658 @ifset installchapter
1659 If you don't use No Gnus, you can take @file{password.el} from the
1660 @value{tramp} @file{contrib} directory, see @ref{Installation
1665 @node Connection caching
1666 @section Reusing connection related information
1669 @vindex tramp-persistency-file-name
1670 In order to reduce initial connection time, @value{tramp} stores
1671 connection related information persistently. The variable
1672 @code{tramp-persistency-file-name} keeps the file name where these
1673 information are written. Its default value is
1675 @file{~/.emacs.d/tramp}.
1678 @file{~/.xemacs/tramp}.
1680 It is recommended to choose a local file name.
1682 @value{tramp} reads this file during startup, and writes it when
1683 exiting @value{emacsname}. You can simply remove this file if
1684 @value{tramp} shall be urged to recompute these information next
1685 @value{emacsname} startup time.
1687 Using such persistent information can be disabled by setting
1688 @code{tramp-persistency-file-name} to @code{nil}.
1690 Once consequence of reusing connection related information is that
1691 @var{tramp} needs to distinguish hosts. If you, for example, run a
1692 local @code{sshd} on port 3001, which tunnels @command{ssh} to another
1693 host, you could access both @file{@trampfn{ssh, , localhost,}} and
1694 @file{@trampfn{ssh, , localhost#3001,}}. @var{tramp} would use the
1695 same host related information (like paths, Perl variants, etc) for
1696 both connections, although the information is valid only for one of
1699 In order to avoid trouble, you must use another host name for one of
1700 the connections, like introducing a @option{Host} section in
1701 @file{~/.ssh/config} (@pxref{Frequently Asked Questions}) or applying
1702 multiple hops (@pxref{Multi-hops}).
1704 When @value{tramp} detects a changed operating system version on a
1705 remote host (via the command @command{uname -sr}), it flushes all
1706 connection related information for this host, and opens the
1710 @node Remote Programs
1711 @section How @value{tramp} finds and uses programs on the remote machine
1713 @value{tramp} depends on a number of programs on the remote host in order to
1714 function, including @command{ls}, @command{test}, @command{find} and
1717 In addition to these required tools, there are various tools that may be
1718 required based on the connection method. See @ref{Inline methods} and
1719 @ref{External methods} for details on these.
1721 Certain other tools, such as @command{perl} (or @command{perl5}) and
1722 @command{grep} will be used if they can be found. When they are
1723 available, they are used to improve the performance and accuracy of
1726 @vindex tramp-remote-path
1727 @vindex tramp-default-remote-path
1728 @vindex tramp-own-remote-path
1729 @defopt tramp-remote-path
1730 When @value{tramp} connects to the remote machine, it searches for the
1731 programs that it can use. The variable @code{tramp-remote-path}
1732 controls the directories searched on the remote machine.
1734 By default, this is set to a reasonable set of defaults for most
1735 machines. The symbol @code{tramp-default-remote-path} is a place
1736 holder, it is replaced by the list of directories received via the
1737 command @command{getconf PATH} on your remote machine. For example,
1738 on Debian GNU/Linux this is @file{/bin:/usr/bin}, whereas on Solaris
1739 this is @file{/usr/xpg4/bin:/usr/ccs/bin:/usr/bin:/opt/SUNWspro/bin}.
1740 It is recommended to apply this symbol on top of
1741 @code{tramp-remote-path}.
1743 It is possible, however, that your local (or remote ;) system
1744 administrator has put the tools you want in some obscure local
1747 In this case, you can still use them with @value{tramp}. You simply
1748 need to add code to your @file{.emacs} to add the directory to the
1749 remote path. This will then be searched by @value{tramp} when you
1750 connect and the software found.
1752 To add a directory to the remote search path, you could use code such
1756 @i{;; We load @value{tramp} to define the variable.}
1758 @i{;; We have @command{perl} in "/usr/local/perl/bin"}
1759 (add-to-list 'tramp-remote-path "/usr/local/perl/bin")
1762 Another possibility is to reuse the path settings of your remote
1763 account when you log in. Usually, these settings are overwritten,
1764 because they might not be useful for @value{tramp}. The place holder
1765 @code{tramp-own-remote-path} preserves these settings. You can
1769 (add-to-list 'tramp-remote-path 'tramp-own-remote-path)
1773 @value{tramp} caches several information, like the Perl binary
1774 location. The changed remote search path wouldn't affect these
1775 settings. In order to force @value{tramp} to recompute these values,
1776 you must exit @value{emacsname}, remove your persistency file
1777 (@pxref{Connection caching}), and restart @value{emacsname}.
1780 @node Remote shell setup
1781 @section Remote shell setup hints
1782 @cindex remote shell setup
1783 @cindex @file{.profile} file
1784 @cindex @file{.login} file
1785 @cindex shell init files
1787 As explained in the @ref{Overview} section, @value{tramp} connects to the
1788 remote host and talks to the shell it finds there. Of course, when you
1789 log in, the shell executes its init files. Suppose your init file
1790 requires you to enter the birth date of your mother; clearly @value{tramp}
1791 does not know this and hence fails to log you in to that host.
1793 There are different possible strategies for pursuing this problem. One
1794 strategy is to enable @value{tramp} to deal with all possible situations.
1795 This is a losing battle, since it is not possible to deal with
1796 @emph{all} situations. The other strategy is to require you to set up
1797 the remote host such that it behaves like @value{tramp} expects. This might
1798 be inconvenient because you have to invest a lot of effort into shell
1799 setup before you can begin to use @value{tramp}.
1801 The package, therefore, pursues a combined approach. It tries to
1802 figure out some of the more common setups, and only requires you to
1803 avoid really exotic stuff. For example, it looks through a list of
1804 directories to find some programs on the remote host. And also, it
1805 knows that it is not obvious how to check whether a file exists, and
1806 therefore it tries different possibilities. (On some hosts and
1807 shells, the command @command{test -e} does the trick, on some hosts
1808 the shell builtin doesn't work but the program @command{/usr/bin/test
1809 -e} or @command{/bin/test -e} works. And on still other hosts,
1810 @command{ls -d} is the right way to do this.)
1812 Below you find a discussion of a few things that @value{tramp} does not deal
1813 with, and that you therefore have to set up correctly.
1816 @item @var{shell-prompt-pattern}
1817 @vindex shell-prompt-pattern
1819 After logging in to the remote host, @value{tramp} has to wait for the remote
1820 shell startup to finish before it can send commands to the remote
1821 shell. The strategy here is to wait for the shell prompt. In order to
1822 recognize the shell prompt, the variable @code{shell-prompt-pattern} has
1823 to be set correctly to recognize the shell prompt on the remote host.
1825 Note that @value{tramp} requires the match for @code{shell-prompt-pattern}
1826 to be at the end of the buffer. Many people have something like the
1827 following as the value for the variable: @code{"^[^>$][>$] *"}. Now
1828 suppose your shell prompt is @code{a <b> c $ }. In this case,
1829 @value{tramp} recognizes the @code{>} character as the end of the prompt,
1830 but it is not at the end of the buffer.
1832 @item @var{tramp-shell-prompt-pattern}
1833 @vindex tramp-shell-prompt-pattern
1835 This regular expression is used by @value{tramp} in the same way as
1836 @code{shell-prompt-pattern}, to match prompts from the remote shell.
1837 This second variable exists because the prompt from the remote shell
1838 might be different from the prompt from a local shell---after all,
1839 the whole point of @value{tramp} is to log in to remote hosts as a
1840 different user. The default value of
1841 @code{tramp-shell-prompt-pattern} is the same as the default value of
1842 @code{shell-prompt-pattern}, which is reported to work well in many
1845 @item @var{tramp-password-prompt-regexp}
1846 @vindex tramp-password-prompt-regexp
1847 @vindex tramp-wrong-passwd-regexp
1849 During login, @value{tramp} might be forced to enter a password or a
1850 passphrase. The difference between both is that a password is
1851 requested from the shell on the remote host, while a passphrase is
1852 needed for accessing local authentication information, like your ssh
1855 @var{tramp-password-prompt-regexp} handles the detection of such
1856 requests for English environments. When you use another localization
1857 of your (local or remote) host, you might need to adapt this. Example:
1861 tramp-password-prompt-regexp
1865 '("passphrase" "Passphrase"
1867 "password" "Password"
1869 "passwort" "Passwort"
1871 "mot de passe" "Mot de passe") t)
1875 In parallel, it might also be necessary to adapt
1876 @var{tramp-wrong-passwd-regexp}.
1878 @item @command{tset} and other questions
1879 @cindex Unix command tset
1880 @cindex tset Unix command
1882 Some people invoke the @command{tset} program from their shell startup
1883 scripts which asks the user about the terminal type of the shell.
1884 Maybe some shells ask other questions when they are started.
1885 @value{tramp} does not know how to answer these questions. There are
1886 two approaches for dealing with this problem. One approach is to take
1887 care that the shell does not ask any questions when invoked from
1888 @value{tramp}. You can do this by checking the @env{TERM}
1889 environment variable, it will be set to @code{dumb} when connecting.
1891 @vindex tramp-terminal-type
1892 The variable @code{tramp-terminal-type} can be used to change this value
1895 @vindex tramp-actions-before-shell
1896 The other approach is to teach @value{tramp} about these questions. See
1897 the variable @code{tramp-actions-before-shell}. Example:
1900 (defconst my-tramp-prompt-regexp
1901 (concat (regexp-opt '("Enter the birth date of your mother:") t)
1903 "Regular expression matching my login prompt question.")
1905 (defun my-tramp-action (proc vec)
1906 "Enter \"19000101\" in order to give a correct answer."
1907 (save-window-excursion
1908 (with-current-buffer (tramp-get-connection-buffer vec)
1909 (tramp-message vec 6 "\n%s" (buffer-string))
1910 (tramp-send-string vec "19000101"))))
1912 (add-to-list 'tramp-actions-before-shell
1913 '(my-tramp-prompt-regexp my-tramp-action))
1917 @item Environment variables named like users in @file{.profile}
1919 If you have a user named frumple and set the variable @env{FRUMPLE} in
1920 your shell environment, then this might cause trouble. Maybe rename
1921 the variable to @env{FRUMPLE_DIR} or the like.
1923 This weird effect was actually reported by a @value{tramp} user!
1926 @item Non-Bourne commands in @file{.profile}
1928 After logging in to the remote host, @value{tramp} issues the command
1929 @command{exec /bin/sh}. (Actually, the command is slightly
1930 different.) When @command{/bin/sh} is executed, it reads some init
1931 files, such as @file{~/.shrc} or @file{~/.profile}.
1933 Now, some people have a login shell which is not @code{/bin/sh} but a
1934 Bourne-ish shell such as bash or ksh. Some of these people might put
1935 their shell setup into the files @file{~/.shrc} or @file{~/.profile}.
1936 This way, it is possible for non-Bourne constructs to end up in those
1937 files. Then, @command{exec /bin/sh} might cause the Bourne shell to
1938 barf on those constructs.
1940 As an example, imagine somebody putting @command{export FOO=bar} into
1941 the file @file{~/.profile}. The standard Bourne shell does not
1942 understand this syntax and will emit a syntax error when it reaches
1945 Another example is the tilde (@code{~}) character, say when adding
1946 @file{~/bin} to @env{PATH}. Many Bourne shells will not expand this
1947 character, and since there is usually no directory whose name consists
1948 of the single character tilde, strange things will happen.
1950 What can you do about this?
1952 Well, one possibility is to make sure that everything in
1953 @file{~/.shrc} and @file{~/.profile} on all remote hosts is
1954 Bourne-compatible. In the above example, instead of @command{export
1955 FOO=bar}, you might use @command{FOO=bar; export FOO} instead.
1957 The other possibility is to put your non-Bourne shell setup into some
1958 other files. For example, bash reads the file @file{~/.bash_profile}
1959 instead of @file{~/.profile}, if the former exists. So bash
1960 aficionados just rename their @file{~/.profile} to
1961 @file{~/.bash_profile} on all remote hosts, and Bob's your uncle.
1963 The @value{tramp} developers would like to circumvent this problem, so
1964 if you have an idea about it, please tell us. However, we are afraid
1965 it is not that simple: before saying @command{exec /bin/sh},
1966 @value{tramp} does not know which kind of shell it might be talking
1967 to. It could be a Bourne-ish shell like ksh or bash, or it could be a
1968 csh derivative like tcsh, or it could be zsh, or even rc. If the
1969 shell is Bourne-ish already, then it might be prudent to omit the
1970 @command{exec /bin/sh} step. But how to find out if the shell is
1974 @item Interactive shell prompt
1976 @value{tramp} redefines the shell prompt in order to parse the shell's
1977 output robustly. When calling an interactive shell by @kbd{M-x
1978 shell}, this doesn't look nice.
1980 You can redefine the shell prompt by checking the environment variable
1981 @env{INSIDE_EMACS}, which is set by @value{tramp}, in your startup
1982 script @file{~/.emacs_SHELLNAME}. @env{SHELLNAME} might be the string
1983 @code{bash} or similar, in case of doubt you could set it the
1984 environment variable @env{ESHELL} in your @file{.emacs}:
1987 (setenv "ESHELL" "bash")
1990 Your file @file{~/.emacs_SHELLNAME} could contain code like
1993 # Reset the prompt for remote Tramp shells.
1994 if [ "$@{INSIDE_EMACS/*tramp*/tramp@}" == "tramp" ] ; then
2001 @xref{Interactive Shell, , , @value{emacsdir}}.
2008 @node Android shell setup
2009 @section Android shell setup hints
2010 @cindex android shell setup
2012 Android devices use a restricted shell. They can be accessed via the
2013 @option{adb} method. However, this restricts the access to a USB
2014 connection, and it requires the installation of the Android SDK on the
2017 When an @command{sshd} process runs on the Android device, like
2018 provided by the @code{SSHDroid} app, any @option{ssh}-based method can
2019 be used. However, this requires some special settings.
2021 The default shell @code{/bin/sh} does not exist. Instead, you shall
2022 use just @code{sh}, which invokes the shell installed on the device.
2023 You can instruct @value{tramp} by this form:
2026 (add-to-list 'tramp-connection-properties
2027 (list (regexp-quote "192.168.0.26") "remote-shell" "sh"))
2031 with @samp{192.168.0.26} being the IP address of your Android device.
2033 The user settings for the @code{$PATH} environment variable must be
2034 preserved. Add this setting:
2037 (add-to-list 'tramp-remote-path 'tramp-own-remote-path)
2040 If the Android device is not @samp{rooted}, you must give the shell a
2041 writable directory for temporary files. You could use this setting:
2044 (add-to-list 'tramp-remote-process-environment "TMPDIR=$HOME")
2047 Now you shall be able to open a remote connection with @kbd{C-x C-f
2048 @trampfn{ssh, , 192.168.0.26#2222, }}, given that @command{sshd}
2049 listens on port @samp{2222}.
2052 @node Auto-save and Backup
2053 @section Auto-save and Backup configuration
2057 @vindex backup-directory-alist
2060 @vindex bkup-backup-directory-info
2063 Normally, @value{emacsname} writes backup files to the same directory
2064 as the original files, but this behavior can be changed via the
2067 @code{backup-directory-alist}.
2070 @code{bkup-backup-directory-info}.
2072 In connection with @value{tramp}, this can have unexpected side
2073 effects. Suppose that you specify that all backups should go to the
2074 directory @file{~/.emacs.d/backups/}, and then you edit the file
2075 @file{@trampfn{su, root, localhost, /etc/secretfile}}. The effect is
2076 that the backup file will be owned by you and not by root, thus
2077 possibly enabling others to see it even if they were not intended to
2082 @code{backup-directory-alist}
2085 @code{bkup-backup-directory-info}
2087 is @code{nil} (the default), such problems do not occur.
2089 Therefore, it is useful to set special values for @value{tramp}
2090 files. For example, the following statement effectively `turns off'
2093 @code{backup-directory-alist}
2096 @code{bkup-backup-directory-info}
2098 for @value{tramp} files:
2102 (add-to-list 'backup-directory-alist
2103 (cons tramp-file-name-regexp nil))
2108 (require 'backup-dir)
2109 (add-to-list 'bkup-backup-directory-info
2110 (list tramp-file-name-regexp ""))
2115 It is also possible to disable backups depending on the used method.
2116 The following code disables backups for the @option{su} and
2117 @option{sudo} methods:
2120 (setq backup-enable-predicate
2122 (and (normal-backup-enable-predicate name)
2124 (let ((method (file-remote-p name 'method)))
2125 (when (stringp method)
2126 (member method '("su" "sudo"))))))))
2131 Another possibility is to use the @value{tramp} variable
2133 @code{tramp-backup-directory-alist}.
2136 @code{tramp-bkup-backup-directory-info}.
2138 This variable has the same meaning like
2140 @code{backup-directory-alist}.
2143 @code{bkup-backup-directory-info}.
2145 If a @value{tramp} file is backed up, and DIRECTORY is an absolute
2146 local file name, DIRECTORY is prepended with the @value{tramp} file
2147 name prefix of the file to be backed up.
2154 (add-to-list 'backup-directory-alist
2155 (cons "." "~/.emacs.d/backups/"))
2156 (setq tramp-backup-directory-alist backup-directory-alist)
2161 (require 'backup-dir)
2162 (add-to-list 'bkup-backup-directory-info
2163 (list "." "~/.emacs.d/backups/" 'full-path))
2164 (setq tramp-bkup-backup-directory-info bkup-backup-directory-info)
2169 The backup file name of @file{@trampfn{su, root, localhost,
2170 /etc/secretfile}} would be
2172 @file{@trampfn{su, root, localhost,
2173 ~/.emacs.d/backups/!su:root@@localhost:!etc!secretfile~}}
2176 @file{@trampfn{su, root, localhost,
2177 ~/.emacs.d/backups/![su!root@@localhost]!etc!secretfile~}}
2180 The same problem can happen with auto-saving files.
2182 The variable @code{auto-save-file-name-transforms} keeps information,
2183 on which directory an auto-saved file should go. By default, it is
2184 initialized for @value{tramp} files to the local temporary directory.
2186 On some versions of @value{emacsname}, namely the version built for
2187 Debian GNU/Linux, the variable @code{auto-save-file-name-transforms}
2188 contains the directory where @value{emacsname} was built. A
2189 workaround is to manually set the variable to a sane value.
2191 If auto-saved files should go into the same directory as the original
2192 files, @code{auto-save-file-name-transforms} should be set to @code{nil}.
2194 Another possibility is to set the variable
2195 @code{tramp-auto-save-directory} to a proper value.
2198 For this purpose you can set the variable @code{auto-save-directory}
2203 @node Windows setup hints
2204 @section Issues with Cygwin ssh
2205 @cindex Cygwin, issues
2207 This section needs a lot of work! Please help.
2209 @cindex method sshx with Cygwin
2210 @cindex sshx method with Cygwin
2211 The recent Cygwin installation of @command{ssh} works only with a
2212 Cygwinized @value{emacsname}. You can check it by typing @kbd{M-x
2213 eshell}, and starting @kbd{ssh test.machine}. The problem is evident
2214 if you see a message like this:
2217 Pseudo-terminal will not be allocated because stdin is not a terminal.
2220 Older @command{ssh} versions of Cygwin are told to cooperate with
2221 @value{tramp} selecting @option{sshx} as the connection method. You
2222 can find information about setting up Cygwin in their FAQ at
2223 @uref{http://cygwin.com/faq/}.
2225 @cindex method scpx with Cygwin
2226 @cindex scpx method with Cygwin
2227 If you wish to use the @option{scpx} connection method, then you might
2228 have the problem that @value{emacsname} calls @command{scp} with a
2229 Windows filename such as @code{c:/foo}. The Cygwin version of
2230 @command{scp} does not know about Windows filenames and interprets
2231 this as a remote filename on the host @code{c}.
2233 One possible workaround is to write a wrapper script for @option{scp}
2234 which converts the Windows filename to a Cygwinized filename.
2236 @cindex Cygwin and ssh-agent
2237 @cindex SSH_AUTH_SOCK and @value{emacsname} on Windows
2238 If you want to use either @option{ssh} based method on Windows, then
2239 you might encounter problems with @command{ssh-agent}. Using this
2240 program, you can avoid typing the pass-phrase every time you log in.
2241 However, if you start @value{emacsname} from a desktop shortcut, then
2242 the environment variable @env{SSH_AUTH_SOCK} is not set and so
2243 @value{emacsname} and thus @value{tramp} and thus @command{ssh} and
2244 @command{scp} started from @value{tramp} cannot communicate with
2245 @command{ssh-agent}. It works better to start @value{emacsname} from
2248 If anyone knows how to start @command{ssh-agent} under Windows in such a
2249 way that desktop shortcuts can profit, please holler. I don't really
2250 know anything at all about Windows@dots{}
2254 @chapter Using @value{tramp}
2255 @cindex using @value{tramp}
2257 Once you have installed @value{tramp} it will operate fairly
2258 transparently. You will be able to access files on any remote machine
2259 that you can log in to as though they were local.
2261 Files are specified to @value{tramp} using a formalized syntax specifying the
2262 details of the system to connect to. This is similar to the syntax used
2263 by the @value{ftppackagename} package.
2266 Something that might happen which surprises you is that
2267 @value{emacsname} remembers all your keystrokes, so if you see a
2268 password prompt from @value{emacsname}, say, and hit @kbd{@key{RET}}
2269 twice instead of once, then the second keystroke will be processed by
2270 @value{emacsname} after @value{tramp} has done its thing. Why, this
2271 type-ahead is normal behavior, you say. Right you are, but be aware
2272 that opening a remote file might take quite a while, maybe half a
2273 minute when a connection needs to be opened. Maybe after half a
2274 minute you have already forgotten that you hit that key!
2277 * Filename Syntax:: @value{tramp} filename conventions.
2278 * Alternative Syntax:: URL-like filename syntax.
2279 * Filename completion:: Filename completion.
2280 * Ad-hoc multi-hops:: Declaring multiple hops in the file name.
2281 * Remote processes:: Integration with other @value{emacsname} packages.
2282 * Cleanup remote connections:: Cleanup remote connections.
2286 @node Filename Syntax
2287 @section @value{tramp} filename conventions
2288 @cindex filename syntax
2289 @cindex filename examples
2291 To access the file @var{localname} on the remote machine @var{machine}
2292 you would specify the filename @file{@trampfn{, , machine,
2293 localname}}. This will connect to @var{machine} and transfer the file
2294 using the default method. @xref{Default Method}.
2296 Some examples of @value{tramp} filenames are shown below.
2299 @item @trampfn{, , melancholia, .emacs}
2300 Edit the file @file{.emacs} in your home directory on the machine
2303 @item @trampfn{, , melancholia.danann.net, .emacs}
2304 This edits the same file, using the fully qualified domain name of
2307 @item @trampfn{, , melancholia, ~/.emacs}
2308 This also edits the same file; the @file{~} is expanded to your
2309 home directory on the remote machine, just like it is locally.
2311 @item @trampfn{, , melancholia, ~daniel/.emacs}
2312 This edits the file @file{.emacs} in the home directory of the user
2313 @code{daniel} on the machine @code{melancholia}. The @file{~<user>}
2314 construct is expanded to the home directory of that user on the remote
2317 @item @trampfn{, , melancholia, /etc/squid.conf}
2318 This edits the file @file{/etc/squid.conf} on the machine
2323 @var{machine} can also be an IPv4 or IPv6 address, like in
2324 @file{@trampfn{, , 127.0.0.1, .emacs}} or @file{@trampfn{, ,
2325 @value{ipv6prefix}::1@value{ipv6postfix}, .emacs}}.
2327 For syntactical reasons, IPv6 addresses must be embedded in square
2328 brackets @file{@value{ipv6prefix}} and @file{@value{ipv6postfix}}.
2331 Unless you specify a different name to use, @value{tramp} will use the
2332 current local user name as the remote user name to log in with. If you
2333 need to log in as a different user, you can specify the user name as
2334 part of the filename.
2336 To log in to the remote machine as a specific user, you use the syntax
2337 @file{@trampfn{, user, machine, path/to.file}}. That means that
2338 connecting to @code{melancholia} as @code{daniel} and editing
2339 @file{.emacs} in your home directory you would specify
2340 @file{@trampfn{, daniel, melancholia, .emacs}}.
2342 It is also possible to specify other file transfer methods
2343 (@pxref{Inline methods}, @pxref{External methods}) as part of the
2346 This is done by putting the method before the user and host name, as
2347 in @file{@value{prefix}@var{method}@value{postfixhop}} (Note the
2351 This is done by replacing the initial @file{@value{prefix}} with
2352 @file{@value{prefix}<method>@value{postfixhop}}. (Note the trailing
2355 The user, machine and file specification remain the same.
2357 So, to connect to the machine @code{melancholia} as @code{daniel},
2358 using the @option{ssh} method to transfer files, and edit
2359 @file{.emacs} in my home directory I would specify the filename
2360 @file{@trampfn{ssh, daniel, melancholia, .emacs}}.
2362 Finally, for some methods it is possible to specify a different port
2363 number than the default one, given by the method. This is specified
2364 by adding @file{#<port>} to the host name, like in @file{@trampfn{ssh,
2365 daniel, melancholia#42, .emacs}}.
2367 Note that @value{tramp} supports only filenames encoded in unibyte.
2370 @node Alternative Syntax
2371 @section URL-like filename syntax
2372 @cindex filename syntax
2373 @cindex filename examples
2375 Additionally to the syntax described in the previous chapter, it is
2376 possible to use a URL-like syntax for @value{tramp}. This can be
2377 switched on by customizing the variable @code{tramp-syntax}. Please
2378 note that this feature is experimental for the time being.
2380 The variable @code{tramp-syntax} must be set before requiring @value{tramp}:
2383 (setq tramp-syntax 'url)
2387 Then, a @value{tramp} filename would look like this:
2388 @file{/@var{method}://@var{user}@@@var{machine}:@var{port}/@var{path/to.file}}.
2389 @file{/@var{method}://} is mandatory, all other parts are optional.
2390 @file{:@var{port}} is useful for methods only who support this.
2392 The last example from the previous section would look like this:
2393 @file{/ssh://daniel@@melancholia/.emacs}.
2395 For the time being, @code{tramp-syntax} can have the following values:
2399 @item @code{ftp}---That is the default syntax
2400 @item @code{url}---URL-like syntax
2403 @item @code{sep}---That is the default syntax
2404 @item @code{url}---URL-like syntax
2405 @item @code{ftp}---EFS-like syntax
2410 @node Filename completion
2411 @section Filename completion
2412 @cindex filename completion
2414 Filename completion works with @value{tramp} for completion of method
2415 names, of user names and of machine names as well as for completion of
2416 file names on remote machines.
2418 In order to enable this, partial completion must be activated in your
2421 @xref{Completion Options, , , @value{emacsdir}}.
2425 If you, for example, type @kbd{C-x C-f @value{prefix}t
2426 @key{TAB}}, @value{tramp} might give you as result the choice for
2429 @multitable {@trampfn{telnet, , melancholia.danann.net,}} {@trampfn{telnet, , 192.168.0.1,}}
2431 @item @value{prefixhop}telnet@value{postfixhop} @tab tmp/
2432 @item @value{prefixhop}toto@value{postfix} @tab
2435 @item @value{prefixhop}telnet@value{postfixhop} @tab @value{prefixhop}toto@value{postfix}
2440 @samp{@value{prefixhop}telnet@value{postfixhop}}
2441 is a possible completion for the respective method,
2443 @samp{tmp/} stands for the directory @file{/tmp} on your local
2446 and @samp{@value{prefixhop}toto@value{postfix}}
2447 might be a host @value{tramp} has detected in your @file{~/.ssh/known_hosts}
2448 file (given you're using default method @option{ssh}).
2450 If you go on to type @kbd{e @key{TAB}}, the minibuffer is completed to
2451 @samp{@value{prefix}telnet@value{postfixhop}}.
2452 Next @kbd{@key{TAB}} brings you all machine names @value{tramp} detects in
2453 your @file{/etc/hosts} file, let's say
2456 @multitable {@trampfn{telnet, , melancholia.danann.net,}} {@trampfn{telnet, , 192.168.0.1,}}
2457 @item @trampfn{telnet, , 127.0.0.1,} @tab @trampfn{telnet, , 192.168.0.1,}
2458 @item @trampfn{telnet, , @value{ipv6prefix}::1@value{ipv6postfix},} @tab @trampfn{telnet, , localhost,}
2459 @item @trampfn{telnet, , melancholia.danann.net,} @tab @trampfn{telnet, , melancholia,}
2463 Now you can choose the desired machine, and you can continue to
2464 complete file names on that machine.
2466 If the configuration files (@pxref{Customizing Completion}), which
2467 @value{tramp} uses for analysis of completion, offer user names, those user
2468 names will be taken into account as well.
2470 Remote machines which have been visited in the past and kept
2471 persistently (@pxref{Connection caching}) will be offered too.
2473 Once the remote machine identification is completed, it comes to
2474 filename completion on the remote host. This works pretty much like
2475 for files on the local host, with the exception that minibuffer
2476 killing via a double-slash works only on the filename part, except
2477 that filename part starts with @file{//}.
2479 A triple-slash stands for the default behavior.
2482 @xref{Minibuffer File, , , @value{emacsdir}}.
2490 @kbd{C-x C-f @trampfn{telnet, , melancholia, /usr/local/bin//etc} @key{TAB}}
2491 @print{} @trampfn{telnet, , melancholia, /etc}
2493 @kbd{C-x C-f @trampfn{telnet, , melancholia, //etc} @key{TAB}}
2496 @kbd{C-x C-f @trampfn{telnet, , melancholia, /usr/local/bin///etc} @key{TAB}}
2501 @kbd{C-x C-f @trampfn{telnet, , melancholia, /usr/local/bin//}}
2502 @print{} @trampfn{telnet, , melancholia, /}
2504 @kbd{C-x C-f @trampfn{telnet, , melancholia, //}}
2509 A remote directory might have changed its contents out of
2510 @value{emacsname} control, for example by creation or deletion of
2511 files by other processes. Therefore, during filename completion, the
2512 remote directory contents are reread regularly in order to detect such
2513 changes, which would be invisible otherwise (@pxref{Connection caching}).
2515 @defopt tramp-completion-reread-directory-timeout
2516 This variable defines the number of seconds since last remote command
2517 before rereading a directory contents. A value of 0 would require an
2518 immediate reread during filename completion, @code{nil} means to use
2519 always cached values for the directory contents.
2523 @node Ad-hoc multi-hops
2524 @section Declaring multiple hops in the file name
2525 @cindex multi-hop, ad-hoc
2526 @cindex proxy hosts, ad-hoc
2528 Multiple hops are configured with the variable
2529 @code{tramp-default-proxies-alist} (@pxref{Multi-hops}). However,
2530 sometimes it is desirable to reach a remote host immediately, without
2531 configuration changes. This can be reached by an ad-hoc specification
2534 A proxy looks like a remote file name specification without the local
2535 file name part. It is prepended to the target remote file name,
2536 separated by @samp{|}. As an example, a remote file on
2537 @samp{you@@remotehost}, passing the proxy @samp{bird@@bastion}, could
2541 @c @kbd{C-x C-f @trampfn{ssh@value{postfixhop}bird@@bastion|ssh, you,
2542 @c remotehost, /path}}
2543 @kbd{C-x C-f @value{prefix}ssh@value{postfixhop}bird@@bastion|ssh@value{postfixhop}you@@remotehost@value{postfix}/path}
2546 Multiple hops can be cascaded, separating all proxies by @samp{|}.
2547 The proxies can also contain the patterns @code{%h} or @code{%u}.
2549 The ad-hoc definition is added on the fly to
2550 @code{tramp-default-proxies-alist}. Therefore, during the lifetime of
2551 the @value{emacsname} session it is not necessary to enter this ad-hoc
2552 specification, again. The remote file name @samp{@trampfn{ssh, you,
2553 remotehost, /path}} would be sufficient from now on.
2555 @vindex tramp-save-ad-hoc-proxies
2556 @defopt tramp-save-ad-hoc-proxies
2557 This customer option controls whether ad-hoc definitions are kept
2558 persistently in @code{tramp-default-proxies-alist}. That means, those
2559 definitions are available also for future @value{emacsname} sessions.
2563 @node Remote processes
2564 @section Integration with other @value{emacsname} packages
2568 @value{tramp} supports running processes on a remote host. This
2569 allows to exploit @value{emacsname} packages without modification for
2570 remote file names. It does not work for the @option{ftp} method.
2571 Association of a pty, as specified in @code{start-file-process}, is
2574 @code{process-file} and @code{start-file-process} work on the remote
2575 host when the variable @code{default-directory} is remote:
2578 (let ((default-directory "/ssh:remote.host:"))
2579 (start-file-process "grep" (get-buffer-create "*grep*")
2580 "/bin/sh" "-c" "grep -e tramp *"))
2584 If the remote host is mounted via GVFS (see @ref{GVFS based methods}),
2585 the remote filesystem is mounted locally. Therefore, there are no
2586 remote processes; all processes run still locally on your machine with
2587 an adapted @code{default-directory}. This section does not apply for
2588 such connection methods.
2591 Remote processes are started when a corresponding command is executed
2592 from a buffer belonging to a remote file or directory. Up to now, the
2593 packages @file{compile.el} (commands like @code{compile} and
2594 @code{grep}) and @file{gud.el} (@code{gdb} or @code{perldb}) have been
2595 integrated. Integration of further packages is planned, any help for
2598 When your program is not found in the default search path
2599 @value{tramp} sets on the remote machine, you should either use an
2600 absolute path, or extend @code{tramp-remote-path} (see @ref{Remote
2604 (add-to-list 'tramp-remote-path "~/bin")
2605 (add-to-list 'tramp-remote-path "/appli/pub/bin")
2608 The environment for your program can be adapted by customizing
2609 @code{tramp-remote-process-environment}. This variable is a list of
2610 strings. It is structured like @code{process-environment}. Each
2611 element is a string of the form @code{"ENVVARNAME=VALUE"}. An entry
2612 @code{"ENVVARNAME="} disables the corresponding environment variable,
2613 which might have been set in your init file like @file{~/.profile}.
2616 Adding an entry can be performed via @code{add-to-list}:
2619 (add-to-list 'tramp-remote-process-environment "JAVA_HOME=/opt/java")
2622 Changing or removing an existing entry is not encouraged. The default
2623 values are chosen for proper @value{tramp} work. Nevertheless, if for
2624 example a paranoid system administrator disallows changing the
2625 @env{HISTORY} environment variable, you can customize
2626 @code{tramp-remote-process-environment}, or you can apply the
2627 following code in your @file{.emacs}:
2630 (let ((process-environment tramp-remote-process-environment))
2631 (setenv "HISTORY" nil)
2632 (setq tramp-remote-process-environment process-environment))
2635 If you use other @value{emacsname} packages which do not run
2636 out-of-the-box on a remote host, please let us know. We will try to
2637 integrate them as well. @xref{Bug Reports}.
2640 @subsection Running remote programs that create local X11 windows
2642 If you want to run a remote program, which shall connect the X11
2643 server you are using with your local host, you can set the
2644 @env{DISPLAY} environment variable on the remote host:
2647 (add-to-list 'tramp-remote-process-environment
2648 (format "DISPLAY=%s" (getenv "DISPLAY")))
2652 @code{(getenv "DISPLAY")} shall return a string containing a host
2653 name, which can be interpreted on the remote host; otherwise you might
2654 use a fixed host name. Strings like @code{:0} cannot be used properly
2657 Another trick might be that you put @code{ForwardX11 yes} or
2658 @code{ForwardX11Trusted yes} to your @file{~/.ssh/config} file for
2662 @subsection Running @code{shell} on a remote host
2665 Calling @kbd{M-x shell} in a buffer related to a remote host runs the
2666 local shell as defined in @option{shell-file-name}. This might be
2667 also a valid path name for a shell to be applied on the remote host,
2668 but it will fail at least when your local and remote hosts belong to
2669 different system types, like @samp{windows-nt} and @samp{gnu/linux}.
2671 You must set the variable @option{explicit-shell-file-name} to the
2672 shell path name on the remote host, in order to start that shell on
2676 Starting with Emacs 24 this won't be necessary, if you call
2677 @code{shell} interactively. You will be asked for the remote shell
2678 path, if you are on a remote buffer, and if
2679 @option{explicit-shell-file-name} is equal to @code{nil}.
2683 @subsection Running @code{shell-command} on a remote host
2684 @cindex shell-command
2686 @code{shell-command} allows to execute commands in a shell, either
2687 synchronously, either asynchronously. This works also on remote
2691 @kbd{C-x C-f @trampfn{sudo, , , } @key{RET}}
2692 @kbd{M-! tail -f /var/log/syslog.log & @key{RET}}
2695 You will see the buffer @file{*Async Shell Command*}, containing the
2696 continuous output of the @command{tail} command.
2699 A similar behaviour can be reached by @kbd{M-x auto-revert-tail-mode},
2704 @subsection Running @code{eshell} on a remote host
2707 @value{tramp} is integrated into @file{eshell.el}. That is, you can
2708 open an interactive shell on your remote host, and run commands there.
2709 After you have started @kbd{M-x eshell}, you could perform commands
2713 @b{~ $} cd @trampfn{sudo, , , /etc} @key{RET}
2714 @b{@trampfn{sudo, root, host, /etc} $} hostname @key{RET}
2716 @b{@trampfn{sudo, root, host, /etc} $} id @key{RET}
2717 uid=0(root) gid=0(root) groups=0(root)
2718 @b{@trampfn{sudo, root, host, /etc} $} find-file shadow @key{RET}
2720 @b{@trampfn{sudo, root, host, /etc} $}
2724 Since @value{emacsname} 23.2, @code{eshell} has also an own
2725 implementation of the @code{su} and @code{sudo} commands. Both
2726 commands change the default directory of the @file{*eshell*} buffer to
2727 the value related to the user the command has switched to. This works
2728 even on remote hosts, adding silently a corresponding entry to the
2729 variable @code{tramp-default-proxies-alist} (@pxref{Multi-hops}):
2732 @b{~ $} cd @trampfn{ssh, user, remotehost, /etc} @key{RET}
2733 @b{@trampfn{ssh, user, remotehost, /etc} $} find-file shadow @key{RET}
2734 File is not readable: @trampfn{ssh, user, remotehost, /etc/shadow}
2735 @b{@trampfn{ssh, user, remotehost, /etc} $} sudo find-file shadow @key{RET}
2738 @b{@trampfn{ssh, user, remotehost, /etc} $} su - @key{RET}
2739 @b{@trampfn{su, root, remotehost, /root} $} id @key{RET}
2740 uid=0(root) gid=0(root) groups=0(root)
2741 @b{@trampfn{su, root, remotehost, /root} $}
2746 @anchor{Running a debugger on a remote host}
2747 @subsection Running a debugger on a remote host
2752 @file{gud.el} offers an unified interface to several symbolic
2756 (@ref{Debuggers, , , @value{emacsdir}}).
2759 With @value{tramp}, it is possible to debug programs on
2760 remote hosts. You can call @code{gdb} with a remote file name:
2763 @kbd{M-x gdb @key{RET}}
2764 @b{Run gdb (like this):} gdb --annotate=3 @trampfn{ssh, , host, ~/myprog} @key{RET}
2767 The file name can also be relative to a remote default directory.
2768 Given you are in a buffer that belongs to the remote directory
2769 @trampfn{ssh, , host, /home/user}, you could call
2772 @kbd{M-x perldb @key{RET}}
2773 @b{Run perldb (like this):} perl -d myprog.pl @key{RET}
2776 It is not possible to use just the absolute local part of a remote
2777 file name as program to debug, like @kbd{perl -d
2778 /home/user/myprog.pl}, though.
2780 Arguments of the program to be debugged are taken literally. That
2781 means, file names as arguments must be given as ordinary relative or
2782 absolute file names, without any remote specification.
2785 @subsection Running remote processes on Windows hosts
2789 With the help of the @command{winexe} it is possible tu run processes
2790 on a remote Windows host. @value{tramp} has implemented this for
2791 @code{process-file} and @code{start-file-process}.
2793 The variable @code{tramp-smb-winexe-program} must contain the file
2794 name of your local @command{winexe} command. On the remote host,
2795 Powershell V2.0 must be installed; it is used to run the remote
2798 In order to open a remote shell on the Windows host via @kbd{M-x
2799 shell}, you must set the variables @option{explicit-shell-file-name}
2800 and @option{explicit-*-args}. If you want, for example, run
2801 @command{cmd}, you must set:
2804 (setq explicit-shell-file-name "cmd"
2805 explicit-cmd-args '("/q"))
2809 In case of running @command{powershell} as remote shell, the settings are
2812 (setq explicit-shell-file-name "powershell"
2813 explicit-powershell-args '("-file" "-"))
2817 @node Cleanup remote connections
2818 @section Cleanup remote connections
2821 Sometimes it is useful to cleanup remote connections. The following
2822 commands support this.
2824 @deffn Command tramp-cleanup-connection vec
2825 This command flushes all connection related objects. @option{vec} is
2826 the internal representation of a remote connection. Called
2827 interactively, the command offers all active remote connections in the
2828 minibuffer as remote file name prefix like @file{@trampfn{method,
2829 user, host, }}. The cleanup includes password cache (@pxref{Password
2830 handling}), file cache, connection cache (@pxref{Connection caching}),
2834 @deffn Command tramp-cleanup-this-connection
2835 This command flushes all objects of the current buffer's remote
2836 connection. The same objects are removed as in
2837 @code{tramp-cleanup-connection}.
2840 @deffn Command tramp-cleanup-all-connections
2841 This command flushes objects for all active remote connections. The
2842 same objects are removed as in @code{tramp-cleanup-connection}.
2845 @deffn Command tramp-cleanup-all-buffers
2846 Like in @code{tramp-cleanup-all-connections}, all remote connections
2847 are cleaned up. Additionally all buffers, which are related to a
2848 remote connection, are killed.
2853 @chapter Reporting Bugs and Problems
2856 Bugs and problems with @value{tramp} are actively worked on by the
2857 development team. Feature requests and suggestions are also more than
2860 The @value{tramp} mailing list is a great place to get information on
2861 working with @value{tramp}, solving problems and general discussion
2862 and advice on topics relating to the package. It is moderated so
2863 non-subscribers can post but messages will be delayed, possibly up to
2864 48 hours (or longer in case of holidays), until the moderator approves
2867 The mailing list is at @email{tramp-devel@@gnu.org}. Messages sent to
2868 this address go to all the subscribers. This is @emph{not} the address
2869 to send subscription requests to.
2871 Subscribing to the list is performed via
2872 @uref{http://lists.gnu.org/mailman/listinfo/tramp-devel/,
2873 the @value{tramp} Mail Subscription Page}.
2876 To report a bug in @value{tramp}, you should execute @kbd{M-x
2877 tramp-bug}. This will automatically generate a buffer with the details
2878 of your system and @value{tramp} version.
2880 When submitting a bug report, please try to describe in excruciating
2881 detail the steps required to reproduce the problem, the setup of the
2882 remote machine and any special conditions that exist. You should also
2883 check that your problem is not described already in @xref{Frequently
2886 If you can identify a minimal test case that reproduces the problem,
2887 include that with your bug report. This will make it much easier for
2888 the development team to analyze and correct the problem.
2890 Sometimes, there might be also problems due to Tramp caches. Flush
2891 all caches before running the test, @ref{Cleanup remote connections}.
2893 Before reporting the bug, you should set the verbosity level to 6
2894 (@pxref{Traces and Profiles, Traces}) in the @file{~/.emacs} file and
2895 repeat the bug. Then, include the contents of the @file{*tramp/foo*}
2896 and @file{*debug tramp/foo*} buffers in your bug report. A verbosity
2897 level greater than 6 will produce a very huge debug buffer, which is
2898 mostly not necessary for the analysis.
2900 Please be aware that, with a verbosity level of 6 or greater, the
2901 contents of files and directories will be included in the debug
2902 buffer. Passwords you've typed will never be included there.
2905 @node Frequently Asked Questions
2906 @chapter Frequently Asked Questions
2907 @cindex frequently asked questions
2912 Where can I get the latest @value{tramp}?
2914 @value{tramp} is available under the URL below.
2917 @uref{ftp://ftp.gnu.org/gnu/tramp/}
2920 There is also a Savannah project page.
2923 @uref{http://savannah.gnu.org/projects/tramp/}
2927 Which systems does it work on?
2929 The package has been used successfully on Emacs 22, Emacs 23, Emacs
2930 24, XEmacs 21 (starting with 21.4), and SXEmacs 22.
2932 The package was intended to work on Unix, and it really expects a
2933 Unix-like system on the remote end (except the @option{smb} method),
2934 but some people seemed to have some success getting it to work on MS
2935 Windows XP/Vista/7 @value{emacsname}.
2939 How could I speed up @value{tramp}?
2941 In the backstage, @value{tramp} needs a lot of operations on the
2942 remote host. The time for transferring data from and to the remote
2943 host as well as the time needed to perform the operations there count.
2944 In order to speed up @value{tramp}, one could either try to avoid some
2945 of the operations, or one could try to improve their performance.
2947 Use an external method, like @option{scp}.
2949 Use caching. This is already enabled by default. Information about
2950 the remote host as well as the remote files are cached for reuse. The
2951 information about remote hosts is kept in the file specified in
2952 @code{tramp-persistency-file-name}. Keep this file. If you are
2953 confident that files on remote hosts are not changed out of
2954 @value{emacsname}' control, set @code{remote-file-name-inhibit-cache}
2955 to @code{nil}. Set also @code{tramp-completion-reread-directory-timeout}
2956 to @code{nil}, @ref{Filename completion}.
2958 Disable version control. If you access remote files which are not
2959 under version control, a lot of check operations can be avoided by
2960 disabling VC@. This can be achieved by
2963 (setq vc-ignore-dir-regexp
2964 (format "\\(%s\\)\\|\\(%s\\)"
2965 vc-ignore-dir-regexp
2966 tramp-file-name-regexp))
2969 Disable excessive traces. The default trace level of @value{tramp},
2970 defined in the variable @code{tramp-verbose}, is 3. You should
2971 increase this level only temporarily, hunting bugs.
2975 @value{tramp} does not connect to the remote host
2977 When @value{tramp} does not connect to the remote host, there are three
2978 reasons heading the bug mailing list:
2982 Unknown characters in the prompt
2984 @value{tramp} needs to recognize the prompt on the remote machine
2985 after execution any command. This is not possible when the prompt
2986 contains unknown characters like escape sequences for coloring. This
2987 should be avoided on the remote side. @xref{Remote shell setup}. for
2988 setting the regular expression detecting the prompt.
2990 You can check your settings after an unsuccessful connection by
2991 switching to the @value{tramp} connection buffer @file{*tramp/foo*},
2992 setting the cursor at the top of the buffer, and applying the expression
2995 @kbd{M-: (re-search-forward (concat tramp-shell-prompt-pattern "$"))}
2998 If it fails, or the cursor is not moved at the end of the buffer, your
2999 prompt is not recognized correctly.
3001 A special problem is the zsh, which uses left-hand side and right-hand
3002 side prompts in parallel. Therefore, it is necessary to disable the
3003 zsh line editor on the remote host. You shall add to @file{~/.zshrc}
3004 the following command:
3007 [ $TERM = "dumb" ] && unsetopt zle && PS1='$ '
3010 Furthermore it has been reported, that @value{tramp} (like sshfs,
3011 incidentally) doesn't work with WinSSHD due to strange prompt settings.
3014 Echoed characters after login
3016 When the remote machine opens an echoing shell, there might be control
3017 characters in the welcome message. @value{tramp} tries to suppress
3018 such echoes via the @command{stty -echo} command, but sometimes this
3019 command is not reached, because the echoed output has confused
3020 @value{tramp} already. In such situations it might be helpful to use
3021 the @option{sshx} or @option{scpx} methods, which allocate a pseudo tty.
3022 @xref{Inline methods}.
3025 @value{tramp} doesn't transfer strings with more than 500 characters
3028 On some few systems, the implementation of @code{process-send-string}
3029 seems to be broken for longer strings. It is reported for HP-UX,
3030 FreeBSD and Tru64 Unix, for example. This case, you should customize
3031 the variable @code{tramp-chunksize} to 500. For a description how to
3032 determine whether this is necessary see the documentation of
3033 @code{tramp-chunksize}.
3035 Additionally, it will be useful to set @code{file-precious-flag} to
3036 @code{t} for @value{tramp} files. Then the file contents will be
3037 written into a temporary file first, which is checked for correct
3040 @pxref{Saving Buffers, , , elisp}
3047 (when (file-remote-p default-directory)
3048 (set (make-local-variable 'file-precious-flag) t))))
3054 @value{tramp} does not recognize hung @command{ssh} sessions
3056 When your network connection is down, @command{ssh} sessions might
3057 hang. @value{tramp} cannot detect it safely, because it still sees a
3058 running @command{ssh} process. Timeouts cannot be used as well,
3059 because it cannot be predicted how long a remote command will last,
3060 for example when copying very large files.
3062 Therefore, you must configure the @command{ssh} process to die
3063 in such a case. The following entry in @file{~/.ssh/config} would do
3068 ServerAliveInterval 5
3073 File name completion does not work with @value{tramp}
3075 When you log in to the remote machine, do you see the output of
3076 @command{ls} in color? If so, this may be the cause of your problems.
3078 @command{ls} outputs @acronym{ANSI} escape sequences that your terminal
3079 emulator interprets to set the colors. These escape sequences will
3080 confuse @value{tramp} however.
3082 In your @file{.bashrc}, @file{.profile} or equivalent on the remote
3083 machine you probably have an alias configured that adds the option
3084 @option{--color=yes} or @option{--color=auto}.
3086 You should remove that alias and ensure that a new login @emph{does not}
3087 display the output of @command{ls} in color. If you still cannot use
3088 filename completion, report a bug to the @value{tramp} developers.
3092 File name completion does not work in large directories
3094 @value{tramp} uses globbing for some operations. (Globbing means to use the
3095 shell to expand wildcards such as `*.c'.) This might create long
3096 command lines, especially in directories with many files. Some shells
3097 choke on long command lines, or don't cope well with the globbing
3100 If you have a large directory on the remote end, you may wish to execute
3101 a command like @samp{ls -d * ..?* > /dev/null} and see if it hangs.
3102 Note that you must first start the right shell, which might be
3103 @command{/bin/sh}, @command{ksh} or @command{bash}, depending on which
3104 of those supports tilde expansion.
3108 How can I get notified when @value{tramp} file transfers are complete?
3110 The following snippet can be put in your @file{~/.emacs} file. It
3111 makes @value{emacsname} beep after reading from or writing to the
3115 (defadvice tramp-handle-write-region
3116 (after tramp-write-beep-advice activate)
3117 "Make tramp beep after writing a file."
3121 (defadvice tramp-handle-do-copy-or-rename-file
3122 (after tramp-copy-beep-advice activate)
3123 "Make tramp beep after copying a file."
3127 (defadvice tramp-handle-insert-file-contents
3128 (after tramp-insert-beep-advice activate)
3129 "Make tramp beep after inserting a file."
3137 I'ld like to get a Visual Warning when working in a sudo:ed context
3139 When you are working with @samp{root} privileges, it might be useful
3140 to get an indication in the buffer's modeline. The following code,
3141 tested with @value{emacsname} 22.1, does the job. You should put it
3142 into your @file{~/.emacs}:
3145 (defun my-mode-line-function ()
3146 (when (string-match "^/su\\(do\\)?:" default-directory)
3147 (setq mode-line-format
3148 (format-mode-line mode-line-format 'font-lock-warning-face))))
3150 (add-hook 'find-file-hook 'my-mode-line-function)
3151 (add-hook 'dired-mode-hook 'my-mode-line-function)
3158 I'ld like to see a host indication in the mode line when I'm remote
3160 The following code has been tested with @value{emacsname} 22.1. You
3161 should put it into your @file{~/.emacs}:
3164 (defconst my-mode-line-buffer-identification
3168 (if (file-remote-p default-directory)
3169 (tramp-file-name-host
3170 (tramp-dissect-file-name default-directory))
3172 (if (string-match "^[^0-9][^.]*\\(\\..*\\)" host-name)
3173 (substring host-name 0 (match-beginning 1))
3178 mode-line-buffer-identification
3179 my-mode-line-buffer-identification)
3185 mode-line-buffer-identification
3186 my-mode-line-buffer-identification)))
3189 Since @value{emacsname} 23.1, the mode line contains an indication if
3190 @code{default-directory} for the current buffer is on a remote host.
3191 The corresponding tooltip includes the name of that host. If you
3192 still want the host name as part of the mode line, you can use the
3193 example above, but the @code{:eval} clause can be simplified:
3198 (or (file-remote-p default-directory 'host)
3200 (if (string-match "^[^0-9][^.]*\\(\\..*\\)" host-name)
3201 (substring host-name 0 (match-beginning 1))
3209 My remote host does not understand default directory listing options
3211 @value{emacsname} computes the @command{dired} options depending on
3212 the local host you are working. If your @command{ls} command on the
3213 remote host does not understand those options, you can change them
3218 'dired-before-readin-hook
3220 (when (file-remote-p default-directory)
3221 (setq dired-actual-switches "-al"))))
3227 There's this @file{~/.sh_history} file on the remote host which keeps
3228 growing and growing. What's that?
3230 Sometimes, @value{tramp} starts @command{ksh} on the remote host for
3231 tilde expansion. Maybe @command{ksh} saves the history by default.
3232 @value{tramp} tries to turn off saving the history, but maybe you have
3233 to help. For example, you could put this in your @file{.kshrc}:
3236 if [ -f $HOME/.sh_history ] ; then
3237 /bin/rm $HOME/.sh_history
3239 if [ "$@{HISTFILE-unset@}" != "unset" ] ; then
3242 if [ "$@{HISTSIZE-unset@}" != "unset" ] ; then
3248 @item There are longish file names to type. How to shorten this?
3250 Let's say you need regularly access to @file{@trampfn{ssh, news,
3251 news.my.domain, /opt/news/etc}}, which is boring to type again and
3252 again. The following approaches can be mixed:
3256 @item Use default values for method and user name:
3258 You can define default methods and user names for hosts,
3259 (@pxref{Default Method}, @pxref{Default User}):
3262 (setq tramp-default-method "ssh"
3263 tramp-default-user "news")
3266 The file name left to type would be
3267 @kbd{C-x C-f @trampfn{, , news.my.domain, /opt/news/etc}}.
3269 Note that there are some useful settings already. Accessing your
3270 local host as @samp{root} user, is possible just by @kbd{C-x C-f
3273 @item Use configuration possibilities of your method:
3275 Several connection methods (i.e., the programs used) offer powerful
3276 configuration possibilities (@pxref{Customizing Completion}). In the
3277 given case, this could be @file{~/.ssh/config}:
3281 HostName news.my.domain
3285 The file name left to type would be @kbd{C-x C-f @trampfn{ssh, , xy,
3286 /opt/news/etc}}. Depending on files in your directories, it is even
3287 possible to complete the host name with @kbd{C-x C-f
3288 @value{prefix}ssh@value{postfixhop}x @key{TAB}}.
3290 @item Use environment variables:
3292 File names typed in the minibuffer can be expanded by environment
3293 variables. You can set them outside @value{emacsname}, or even with
3297 (setenv "xy" "@trampfn{ssh, news, news.my.domain, /opt/news/etc/}")
3300 Then you need simply to type @kbd{C-x C-f $xy @key{RET}}, and here you
3301 are. The disadvantage is that you cannot edit the file name, because
3302 environment variables are not expanded during editing in the
3305 @item Define own keys:
3307 You can define your own key sequences in @value{emacsname}, which can
3308 be used instead of @kbd{C-x C-f}:
3312 [(control x) (control y)]
3318 "@trampfn{ssh, news, news.my.domain, /opt/news/etc/}"))))
3321 Simply typing @kbd{C-x C-y} would initialize the minibuffer for
3322 editing with your beloved file name.
3324 See also @uref{http://www.emacswiki.org/cgi-bin/wiki/TrampMode, the
3325 Emacs Wiki} for a more comprehensive example.
3327 @item Define own abbreviation (1):
3329 It is possible to define an own abbreviation list for expanding file
3334 'directory-abbrev-alist
3335 '("^/xy" . "@trampfn{ssh, news, news.my.domain, /opt/news/etc/}"))
3338 This shortens the file opening command to @kbd{C-x C-f /xy
3339 @key{RET}}. The disadvantage is, again, that you cannot edit the file
3340 name, because the expansion happens after entering the file name only.
3342 @item Define own abbreviation (2):
3344 The @code{abbrev-mode} gives more flexibility for editing the
3348 (define-abbrev-table 'my-tramp-abbrev-table
3349 '(("xy" "@trampfn{ssh, news, news.my.domain, /opt/news/etc/}")))
3352 'minibuffer-setup-hook
3355 (setq local-abbrev-table my-tramp-abbrev-table)))
3357 (defadvice minibuffer-complete
3358 (before my-minibuffer-complete activate)
3361 ;; If you use partial-completion-mode
3362 (defadvice PC-do-completion
3363 (before my-PC-do-completion activate)
3367 After entering @kbd{C-x C-f xy @key{TAB}}, the minibuffer is
3368 expanded, and you can continue editing.
3370 @item Use bookmarks:
3372 Bookmarks can be used to visit Tramp files or directories.
3374 @pxref{Bookmarks, , , @value{emacsdir}}
3377 When you have opened @file{@trampfn{ssh, news, news.my.domain,
3378 /opt/news/etc/}}, you should save the bookmark via
3380 @kbd{@key{menu-bar} @key{edit} @key{bookmarks} @key{set}}.
3383 @kbd{@key{menu-bar} @key{view} @key{bookmarks} @key{set}}.
3386 Later on, you can always navigate to that bookmark via
3388 @kbd{@key{menu-bar} @key{edit} @key{bookmarks} @key{jump}}.
3391 @kbd{@key{menu-bar} @key{view} @key{bookmarks} @key{jump}}.
3394 @item Use recent files:
3402 remembers visited places.
3405 @pxref{File Conveniences, , , @value{emacsdir}}
3408 @pxref{recent-files, , , edit-utils}
3412 You could keep remote file names in the recent list without checking
3413 their readability through a remote access:
3420 (recent-files-initialize)
3424 (when (file-remote-p (buffer-file-name))
3425 (recent-files-make-permanent)))
3430 The list of files opened recently is reachable via
3432 @kbd{@key{menu-bar} @key{file} @key{Open Recent}}.
3435 @kbd{@key{menu-bar} @key{Recent Files}}.
3439 @item Use filecache:
3441 @file{filecache} remembers visited places. Add the directory into
3445 (eval-after-load "filecache"
3446 '(file-cache-add-directory
3447 "@trampfn{ssh, news, news.my.domain, /opt/news/etc/}"))
3450 Whenever you want to load a file, you can enter @kbd{C-x C-f
3451 C-@key{TAB}} in the minibuffer. The completion is done for the given
3458 @file{bbdb} has a built-in feature for @value{ftppackagename} files,
3459 which works also for @value{tramp}.
3461 @pxref{bbdb-ftp, Storing FTP sites in the BBDB, , bbdb}
3464 You need to load @file{bbdb}:
3471 Then you can create a BBDB entry via @kbd{M-x bbdb-create-ftp-site}.
3472 Because BBDB is not prepared for @value{tramp} syntax, you must
3473 specify a method together with the user name when needed. Example:
3476 @kbd{M-x bbdb-create-ftp-site @key{RET}}
3477 @b{Ftp Site:} news.my.domain @key{RET}
3478 @b{Ftp Directory:} /opt/news/etc/ @key{RET}
3479 @b{Ftp Username:} ssh@value{postfixhop}news @key{RET}
3480 @b{Company:} @key{RET}
3481 @b{Additional Comments:} @key{RET}
3484 When you have opened your BBDB buffer, you can access such an entry by
3485 pressing the key @key{F}.
3490 I would like to thank all @value{tramp} users who have contributed to
3491 the different recipes!
3496 How can I use @value{tramp} to connect to a remote @value{emacsname}
3499 You can configure Emacs Client doing this.
3501 @xref{Emacs Server, , , @value{emacsdir}}.
3504 On the remote host, you start the Emacs Server:
3508 (setq server-host (system-name)
3513 Make sure that the result of @code{(system-name)} can be resolved on
3514 your local host; otherwise you might use a hard coded IP address.
3516 The resulting file @file{~/.emacs.d/server/server} must be copied to
3517 your local host, at the same location. You can call then the Emacs
3518 Client from the command line:
3521 emacsclient @trampfn{ssh, user, host, /file/to/edit}
3524 @code{user} and @code{host} shall be related to your local host.
3526 If you want to use Emacs Client also as editor for other programs, you
3527 could write a script @file{emacsclient.sh}:
3531 emacsclient @trampfn{ssh, $(whoami), $(hostname --fqdn), $1}
3534 Then you must set the environment variable @env{EDITOR} pointing to
3538 export EDITOR=/path/to/emacsclient.sh
3544 There are packages which call @value{tramp} although I haven't entered
3545 a remote file name ever. I dislike it, how could I disable it?
3547 In general, @value{tramp} functions are used only when
3548 you apply remote file name syntax. However, some packages enable
3549 @value{tramp} on their own.
3555 You could disable @value{tramp} file name completion:
3558 (custom-set-variables
3559 '(ido-enable-tramp-completion nil))
3565 You could disable remote directory tracking mode:
3568 (rlogin-directory-tracking-mode -1)
3574 How can I disable @value{tramp} at all?
3576 Shame on you, why did you read until now?
3581 If you just want to have @value{ftppackagename} as default remote
3582 files access package, you should apply the following code:
3585 (setq tramp-default-method "ftp")
3592 @value{tramp} (and @value{ftppackagename}),
3597 you must set @code{tramp-mode} to @code{nil}:
3600 (setq tramp-mode nil)
3604 Unloading @value{tramp} can be achieved by applying @kbd{M-x
3605 tramp-unload-tramp}.
3607 This resets also the @value{ftppackagename} plugins.
3613 @c For the developer
3614 @node Files directories and localnames
3615 @chapter How file names, directories and localnames are mangled and managed.
3618 * Localname deconstruction:: Breaking a localname into its components.
3620 * External packages:: Integration with external Lisp packages.
3625 @node Localname deconstruction
3626 @section Breaking a localname into its components
3628 @value{tramp} file names are somewhat different, obviously, to ordinary file
3629 names. As such, the lisp functions @code{file-name-directory} and
3630 @code{file-name-nondirectory} are overridden within the @value{tramp}
3633 Their replacements are reasonably simplistic in their approach. They
3634 dissect the filename, call the original handler on the localname and
3635 then rebuild the @value{tramp} file name with the result.
3637 This allows the platform specific hacks in the original handlers to take
3638 effect while preserving the @value{tramp} file name information.
3642 @node External packages
3643 @section Integration with external Lisp packages
3644 @subsection Filename completion.
3646 While reading filenames in the minibuffer, @value{tramp} must decide
3647 whether it completes possible incomplete filenames, or not. Imagine
3648 there is the following situation: You have typed @kbd{C-x C-f
3649 @value{prefix}ssh@value{postfixhop} @key{TAB}}. @value{tramp} cannot
3650 know, whether @option{ssh} is a method or a host name. It checks
3651 therefore the last input character you have typed. If this is
3652 @key{TAB}, @key{SPACE} or @kbd{?}, @value{tramp} assumes that you are
3653 still in filename completion, and it does not connect to the possible
3654 remote host @option{ssh}.
3656 @vindex tramp-completion-mode
3657 External packages, which use other characters for completing filenames
3658 in the minibuffer, must signal this to @value{tramp}. For this case,
3659 the variable @code{tramp-completion-mode} can be bound temporarily to
3660 a non-@code{nil} value.
3663 (let ((tramp-completion-mode t))
3668 @subsection File attributes cache.
3670 When @value{tramp} runs remote processes, files on the remote host
3671 could change their attributes. Consequently, @value{tramp} must flush
3672 its complete cache keeping attributes for all files of the remote host
3675 This is a performance degradation, because the lost file attributes
3676 must be recomputed when needed again. In cases the caller of
3677 @code{process-file} knows that there are no file attribute changes, it
3678 shall let-bind the variable @code{process-file-side-effects} to
3679 @code{nil}. @value{tramp} wouldn't flush the file attributes cache then.
3682 (let (process-file-side-effects)
3686 For asynchronous processes, @value{tramp} flushes the file attributes
3687 cache via a process sentinel. If the caller of
3688 @code{start-file-process} knows that there are no file attribute
3689 changes, it shall set the process sentinel to @code{nil}. In case the
3690 caller defines an own process sentinel, @value{tramp}'s process
3691 sentinel is overwritten. The caller can still flush the file
3692 attributes cache in its process sentinel with this code:
3695 (unless (memq (process-status proc) '(run open))
3696 (dired-uncache remote-directory))
3699 @code{remote-directory} shall be the root directory, where file
3700 attribute changes can happen during the process lifetime.
3701 @value{tramp} traverses all subdirectories, starting at this
3702 directory. Often, it is sufficient to use @code{default-directory} of
3703 the process buffer as root directory.
3707 @node Traces and Profiles
3708 @chapter How to Customize Traces
3710 All @value{tramp} messages are raised with a verbosity level. The
3711 verbosity level can be any number between 0 and 10. Only messages with
3712 a verbosity level less than or equal to @code{tramp-verbose} are
3715 The verbosity levels are
3717 @w{ 0} silent (no @value{tramp} messages at all)
3718 @*@indent @w{ 1} errors
3719 @*@indent @w{ 2} warnings
3720 @*@indent @w{ 3} connection to remote hosts (default verbosity)
3721 @*@indent @w{ 4} activities
3722 @*@indent @w{ 5} internal
3723 @*@indent @w{ 6} sent and received strings
3724 @*@indent @w{ 7} file caching
3725 @*@indent @w{ 8} connection properties
3726 @*@indent @w{ 9} test commands
3727 @*@indent @w{10} traces (huge)
3729 When @code{tramp-verbose} is greater than or equal to 4, the messages
3730 are also written into a @value{tramp} debug buffer. This debug buffer
3731 is useful for analyzing problems; sending a @value{tramp} bug report
3732 should be done with @code{tramp-verbose} set to a verbosity level of at
3733 least 6 (@pxref{Bug Reports}).
3735 The debug buffer is in
3737 @ref{Outline Mode, , , @value{emacsdir}}.
3742 That means, you can change the level of messages to be viewed. If you
3743 want, for example, see only messages up to verbosity level 5, you must
3744 enter @kbd{C-u 6 C-c C-q}.
3746 Other keys for navigating are described in
3747 @ref{Outline Visibility, , , @value{emacsdir}}.
3750 @value{tramp} errors are handled internally in order to raise the
3751 verbosity level 1 messages. When you want to get a Lisp backtrace in
3752 case of an error, you need to set both
3755 (setq debug-on-error t
3759 Sometimes, it might be even necessary to step through @value{tramp}
3760 function call traces. Such traces are enabled by the following code:
3765 (dolist (elt (all-completions "tramp-" obarray 'functionp))
3766 (trace-function-background (intern elt)))
3767 (untrace-function 'tramp-read-passwd)
3768 (untrace-function 'tramp-gw-basic-authentication)
3771 The function call traces are inserted in the buffer
3772 @file{*trace-output*}. @code{tramp-read-passwd} and
3773 @code{tramp-gw-basic-authentication} shall be disabled when the
3774 function call traces are added to @value{tramp}, because both
3775 functions return password strings, which should not be distributed.
3779 @chapter Debatable Issues and What Was Decided
3782 @item The uuencode method does not always work.
3784 Due to the design of @value{tramp}, the encoding and decoding programs
3785 need to read from stdin and write to stdout. On some systems,
3786 @command{uudecode -o -} will read stdin and write the decoded file to
3787 stdout, on other systems @command{uudecode -p} does the same thing.
3788 But some systems have uudecode implementations which cannot do this at
3789 all---it is not possible to call these uudecode implementations with
3790 suitable parameters so that they write to stdout.
3792 Of course, this could be circumvented: the @code{begin foo 644} line
3793 could be rewritten to put in some temporary file name, then
3794 @command{uudecode} could be called, then the temp file could be
3795 printed and deleted.
3797 But I have decided that this is too fragile to reliably work, so on some
3798 systems you'll have to do without the uuencode methods.
3800 @item The @value{tramp} filename syntax differs between Emacs and XEmacs.
3802 The Emacs maintainers wish to use a unified filename syntax for
3803 Ange-FTP and @value{tramp} so that users don't have to learn a new
3804 syntax. It is sufficient to learn some extensions to the old syntax.
3806 For the XEmacs maintainers, the problems caused from using a unified
3807 filename syntax are greater than the gains. The XEmacs package system
3808 uses EFS for downloading new packages. So, obviously, EFS has to be
3809 installed from the start. If the filenames were unified, @value{tramp}
3810 would have to be installed from the start, too.
3813 @strong{Note:} If you'd like to use a similar syntax like
3814 @value{ftppackagename}, you need the following settings in your init
3818 (setq tramp-unified-filenames t)
3822 The autoload of the @value{emacsname} @value{tramp} package must be
3823 disabled. This can be achieved by setting file permissions @code{000}
3824 to the files @file{.../xemacs-packages/lisp/tramp/auto-autoloads.el*}.
3826 In case of unified filenames, all @value{emacsname} download sites are
3827 added to @code{tramp-default-method-alist} with default method
3828 @option{ftp} @xref{Default Method}. These settings shouldn't be
3829 touched for proper working of the @value{emacsname} package system.
3831 The syntax for unified filenames is described in the @value{tramp} manual
3832 for @value{emacsothername}.
3836 @node GNU Free Documentation License
3837 @appendix GNU Free Documentation License
3838 @include doclicense.texi
3840 @node Function Index
3841 @unnumbered Function Index
3844 @node Variable Index
3845 @unnumbered Variable Index
3849 @unnumbered Concept Index
3856 @c * Say something about the .login and .profile files of the remote
3858 @c * Explain how tramp.el works in principle: open a shell on a remote
3859 @c host and then send commands to it.
3860 @c * Use `filename' resp. `file name' consistently.
3861 @c * Use `host' resp. `machine' consistently.
3862 @c * Consistent small or capitalized words especially in menus.