@copying
Copyright @copyright{} 1999, 2000, 2001, 2002, 2003, 2004, 2005,
- 2006, 2007, 2008 Free Software Foundation, Inc.
+2006, 2007, 2008, 2009 Free Software Foundation, Inc.
@quotation
Permission is granted to copy, distribute and/or modify this document
-under the terms of the GNU Free Documentation License, Version 1.2 or
+under the terms of the GNU Free Documentation License, Version 1.3 or
any later version published by the Free Software Foundation; with no
-Invariant Sections, with the Front-Cover texts being ``A GNU
-Manual'', and with the Back-Cover Texts as in (a) below. A copy of the
-license is included in the section entitled ``GNU Free Documentation
-License'' in the Emacs manual.
+Invariant Sections, with the Front-Cover texts being ``A GNU Manual'',
+and with the Back-Cover Texts as in (a) below. A copy of the license
+is included in the section entitled ``GNU Free Documentation License''.
(a) The FSF's Back-Cover Text is: ``You have the freedom to
copy and modify this GNU manual. Buying copies from the FSF
supports it in developing GNU and promoting software freedom.''
-
-This document is part of a collection distributed under the GNU Free
-Documentation License. If you want to distribute this document
-separately from the collection, you can do so by adding a copy of the
-license to the document, as described in section 6 of the license.
@end quotation
@end copying
* Connection types:: Types of connections made to remote machines.
* Inline methods:: Inline methods.
-* External transfer methods:: External transfer methods.
+* External methods:: External methods.
@ifset emacsgw
* Gateway methods:: Gateway methods.
@end ifset
* Multi-hops:: Connecting to a remote host using multiple hops.
* Customizing Methods:: Using Non-Standard Methods.
* Customizing Completion:: Selecting config files for user/host name completion.
-* Password caching:: Reusing passwords for several connections.
+* Password handling:: Reusing passwords for several connections.
* Connection caching:: Reusing connection related information.
* Remote Programs:: How @value{tramp} finds and uses programs on the remote machine.
* Remote shell setup:: Remote shell setup hints.
buffer that's used for communication, then decodes that output to
produce the file contents.
-For out-of-band transfers, @value{tramp} issues a command like the following:
+For external transfers, @value{tramp} issues a command like the
+following:
@example
rcp user@@host:/path/to/remote/file /tmp/tramp.4711
@end example
you are finished, you type @kbd{C-x C-s} to save the buffer.
@item
-Again, @value{tramp} transfers the file contents to the remote host either
-inline or out-of-band. This is the reverse of what happens when reading
-the file.
+Again, @value{tramp} transfers the file contents to the remote host
+either inline or external. This is the reverse of what happens when
+reading the file.
@end itemize
I hope this has provided you with a basic overview of what happens
@menu
* Connection types:: Types of connections made to remote machines.
* Inline methods:: Inline methods.
-* External transfer methods:: External transfer methods.
+* External methods:: External methods.
@ifset emacsgw
* Gateway methods:: Gateway methods.
@end ifset
* Multi-hops:: Connecting to a remote host using multiple hops.
* Customizing Methods:: Using Non-Standard Methods.
* Customizing Completion:: Selecting config files for user/host name completion.
-* Password caching:: Reusing passwords for several connections.
+* Password handling:: Reusing passwords for several connections.
* Connection caching:: Reusing connection related information.
* Remote Programs:: How @value{tramp} finds and uses programs on the remote machine.
* Remote shell setup:: Remote shell setup hints.
differ.
@cindex inline methods
-@cindex external transfer methods
@cindex external methods
-@cindex out-of-band methods
@cindex methods, inline
-@cindex methods, external transfer
-@cindex methods, out-of-band
+@cindex methods, external
Loading or saving a remote file requires that the content of the file
-be transfered between the two machines. The content of the file can be
-transfered over the same connection used to log in to the remote
-machine or the file can be transfered through another connection using
-a remote copy program such as @command{rcp}, @command{scp} or
-@command{rsync}. The former are called @dfn{inline methods}, the
-latter are called @dfn{out-of-band methods} or @dfn{external transfer
-methods} (@dfn{external methods} for short).
-
-The performance of the external transfer methods is generally better
-than that of the inline methods, at least for large files. This is
-caused by the need to encode and decode the data when transferring
-inline.
+be transfered between the two machines. The content of the file can
+be transfered using one of two methods: the @dfn{inline method} over
+the same connection used to log in to the remote machine, or the
+@dfn{external method} through another connection using a remote copy
+program such as @command{rcp}, @command{scp} or @command{rsync}.
+
+The performance of the external methods is generally better than that
+of the inline methods, at least for large files. This is caused by
+the need to encode and decode the data when transferring inline.
The one exception to this rule are the @command{scp} based transfer
methods. While these methods do see better performance when actually
transferring files, the overhead of the cryptographic negotiation at
startup may drown out the improvement in file transfer times.
-External transfer methods should be configured such a way that they
-don't require a password (with @command{ssh-agent}, or such alike).
-Modern @command{scp} implementations offer options to reuse existing
+External methods should be configured such a way that they don't
+require a password (with @command{ssh-agent}, or such alike). Modern
+@command{scp} implementations offer options to reuse existing
@command{ssh} connections, see method @command{scpc}. If it isn't
-possible, you should consider @ref{Password caching}, otherwise you
+possible, you should consider @ref{Password handling}, otherwise you
will be prompted for a password every copy action.
@end table
-@node External transfer methods
-@section External transfer methods
-@cindex methods, external transfer
-@cindex methods, out-of-band
-@cindex external transfer methods
-@cindex out-of-band methods
+@node External methods
+@section External methods
+@cindex methods, external
+@cindex external methods
-The external transfer methods operate through multiple channels, using
-the remote shell connection for many actions while delegating file
+The external methods operate through multiple channels, using the
+remote shell connection for many actions while delegating file
transfers to an external transfer utility.
This saves the overhead of encoding and decoding that multiplexing the
transfer through the one connection has with the inline methods.
-Since external transfer methods need their own overhead opening a new
-channel, all files which are smaller than @var{tramp-copy-size-limit}
-are still transferred with the corresponding inline method. It should
-provide a fair trade-off between both approaches.
+Since external methods need their own overhead opening a new channel,
+all files which are smaller than @var{tramp-copy-size-limit} are still
+transferred with the corresponding inline method. It should provide a
+fair trade-off between both approaches.
@table @asis
@item @option{rcp} --- @command{rsh} and @command{rcp}
Since authorization is done on share level, you will be prompted
always for a password if you access another share on the same host.
-This can be suppressed by @ref{Password caching}.
+This can be suppressed by @ref{Password handling}.
MS Windows uses for authorization both a user name and a domain name.
Because of this, the @value{tramp} syntax has been extended: you can
See the documentation for the variable
@code{tramp-default-method-alist} for more details.
-External transfer methods are normally preferable to inline transfer
-methods, giving better performance.
+External methods are normally preferable to inline methods, giving
+better performance.
@xref{Inline methods}.
-@xref{External transfer methods}.
+@xref{External methods}.
Another consideration with the selection of transfer methods is the
environment you will use them in and, especially when used over the
like to have some guidance, so here I'll try to give you this guidance
without bossing you around. You tell me whether it works @dots{}
-My suggestion is to use an inline method. For large files, out-of-band
-methods might be more efficient, but I guess that most people will want
-to edit mostly small files.
+My suggestion is to use an inline method. For large files, external
+methods might be more efficient, but I guess that most people will
+want to edit mostly small files.
I guess that these days, most people can access a remote machine by
using @command{ssh}. So I suggest that you use the @option{ssh}
People who edit large files may want to consider @option{scpc} instead
of @option{ssh}, or @option{pscp} instead of @option{plink}. These
-out-of-band methods are faster than inline methods for large files.
-Note, however, that out-of-band methods suffer from some limitations.
+external methods are faster than inline methods for large files.
+Note, however, that external methods suffer from some limitations.
Please try first whether you really get a noticeable speed advantage
-from using an out-of-band method! Maybe even for large files, inline
+from using an external method! Maybe even for large files, inline
methods are fast enough.
@end defun
-@node Password caching
+@node Password handling
@section Reusing passwords for several connections.
@cindex passwords
the chosen method does not support access without password prompt
through own configuration.
-By default, @value{tramp} caches the passwords entered by you. They will
-be reused next time if a connection needs them for the same user name
-and host name, independently of the connection method.
+The best recommendation is to use the method's own mechanism for
+password handling. Consider @command{ssh-agent} for @option{ssh}-like
+methods, or @command{pageant} for @option{plink}-like methods.
+
+However, if you cannot apply such native password handling,
+@value{tramp} offers altenatives.
+
+
+@anchor{auth-sources}
+@subsection Using an authentication file
+
+@vindex auth-sources
+The package @file{auth-source.el}, originally developed in No Gnus,
+offers the possibility to read passwords from a file, like FTP does it
+from @file{~/.netrc}. The default authentication file is
+@file{~/.authinfo.gpg}, this can be changed via the variable
+@code{auth-sources}.
+
+@noindent
+A typical entry in the authentication file would be
+
+@example
+machine melancholia port scp login daniel password geheim
+@end example
+
+The port can be any @value{tramp} method (@pxref{Inline methods},
+@pxref{External methods}), to match only this method. When you omit
+the port, you match all @value{tramp} methods.
+
+
+@anchor{password-cache}
+@subsection Caching passwords
+
+If there is no authentication file, @value{tramp} caches the passwords
+entered by you. They will be reused next time if a connection needs
+them for the same user name and host name, independently of the
+connection method.
@vindex password-cache-expiry
Passwords are not saved permanently, that means the password caching
@code{password-cache} (setting it to @code{nil}).
Implementation Note: password caching is based on the package
-@file{password.el} in No Gnus. For the time being, it is activated
-only when this package is seen in the @code{load-path} while loading
+@file{password-cache.el}. For the time being, it is activated only
+when this package is seen in the @code{load-path} while loading
@value{tramp}.
@ifset installchapter
If you don't use No Gnus, you can take @file{password.el} from the
@value{tramp} @file{contrib} directory, see @ref{Installation
parameters}.
@end ifset
-It will be activated mandatory once No Gnus has found its way into
-@value{emacsname}.
@node Connection caching
When @value{tramp} detects a changed operating system version on a
remote host (via the command @command{uname -sr}), it flushes all
-connection related information for this host, quits the execution, and
-displays a message like this:
-
-@example
-Quit: "Connection reset, because remote host changed from `Linux
-2.6.22-13-generic' to `Linux 2.6.22-14-generic'"
-@end example
-
-@noindent
-You can simply open the remote file again in such a case.
+connection related information for this host, and opens the
+connection, again.
@node Remote Programs
In addition to these required tools, there are various tools that may be
required based on the connection method. See @ref{Inline methods} and
-@ref{External transfer methods} for details on these.
+@ref{External methods} for details on these.
Certain other tools, such as @command{perl} (or @command{perl5}) and
@command{grep} will be used if they can be found. When they are
@end table
+@var{machine} can also be an IPv4 or IPv6 address, like in
+@file{@trampfn{, , 127.0.0.1, .emacs}} or @file{@trampfn{, ,
+@value{ipv6prefix}::1@value{ipv6postfix}, .emacs}}.
+@ifset emacs
+For syntactical reasons, IPv6 addresses must be embedded in square
+brackets @file{@value{ipv6prefix}} and @file{@value{ipv6postfix}}.
+@end ifset
+
Unless you specify a different name to use, @value{tramp} will use the
current local user name as the remote user name to log in with. If you
need to log in as a different user, you can specify the user name as
@file{@trampfn{, daniel, melancholia, .emacs}}.
It is also possible to specify other file transfer methods
-(@pxref{Inline methods}, @pxref{External transfer methods}) as part of
-the filename.
+(@pxref{Inline methods}, @pxref{External methods}) as part of the
+filename.
@ifset emacs
This is done by putting the method before the user and host name, as
in @file{@value{prefix}@var{method}@value{postfixhop}} (Note the
@key{TAB}}, @value{tramp} might give you as result the choice for
@example
+@multitable {@trampfn{telnet, , melancholia.danann.net,}} {@trampfn{telnet, , 192.168.0.1,}}
@ifset emacs
-@value{prefixhop}telnet@value{postfixhop} tmp/
-@value{prefixhop}toto@value{postfix}
+@item @value{prefixhop}telnet@value{postfixhop} @tab tmp/
+@item @value{prefixhop}toto@value{postfix} @tab
@end ifset
@ifset xemacs
-@value{prefixhop}telnet@value{postfixhop} @value{prefixhop}toto@value{postfix}
+@item @value{prefixhop}telnet@value{postfixhop} @tab @value{prefixhop}toto@value{postfix}
@end ifset
+@end multitable
@end example
@samp{@value{prefixhop}telnet@value{postfixhop}}
your @file{/etc/hosts} file, let's say
@example
-@trampfn{telnet, , 127.0.0.1,} @trampfn{telnet, , 192.168.0.1,}
-@trampfn{telnet, , localhost,} @trampfn{telnet, , melancholia.danann.net,}
-@trampfn{telnet, , melancholia,}
+@multitable {@trampfn{telnet, , melancholia.danann.net,}} {@trampfn{telnet, , 192.168.0.1,}}
+@item @trampfn{telnet, , 127.0.0.1,} @tab @trampfn{telnet, , 192.168.0.1,}
+@item @trampfn{telnet, , @value{ipv6prefix}::1@value{ipv6postfix},} @tab @trampfn{telnet, , localhost,}
+@item @trampfn{telnet, , melancholia.danann.net,} @tab @trampfn{telnet, , melancholia,}
+@end multitable
@end example
Now you can choose the desired machine, and you can continue to
killing via a double-slash works only on the filename part, except
that filename part starts with @file{//}.
@ifset emacs
-A triple-slash stands for the default behaviour.
+A triple-slash stands for the default behavior.
@end ifset
@ifinfo
@xref{Minibuffer File, , , @value{emacsdir}}.
interactively, the command offers all active remote connections in the
minibuffer as remote file name prefix like @file{@trampfn{method,
user, host, }}. The cleanup includes password cache (@pxref{Password
-caching}), file cache, connection cache (@pxref{Connection caching}),
+handling}), file cache, connection cache (@pxref{Connection caching}),
connection buffers.
@end deffn
In order to speed up @value{tramp}, one could either try to avoid some
of the operations, or one could try to improve their performance.
-Use an external transfer method, like @option{scpc}.
+Use an external method, like @option{scpc}.
Use caching. This is already enabled by default. Information about
the remote host as well as the remote files are cached for reuse. The
@end example
If it fails, or the cursor is not moved at the end of the buffer, your
-prompt is not recognised correctly.
+prompt is not recognized correctly.
A special problem is the zsh, which uses left-hand side and right-hand
side prompts in parallel. Therefore, it is necessary to disable the
@c shells.
@c * Explain how tramp.el works in principle: open a shell on a remote
@c host and then send commands to it.
-@c * Make terminology "inline" vs "out-of-band" consistent.
-@c It seems that "external" is also used instead of "out-of-band".
-
-@c * M. Albinus
-@c ** Use `filename' resp. `file name' consistently.
-@c ** Use `host' resp. `machine' consistently.
-@c ** Consistent small or capitalized words especially in menues.
+@c * Use `filename' resp. `file name' consistently.
+@c * Use `host' resp. `machine' consistently.
+@c * Consistent small or capitalized words especially in menues.
@ignore
arch-tag: f96dd66e-6dd3-4c92-8d77-9c56205ba808