-\versionid $Id: faq.but,v 1.47 2003/05/22 08:43:50 simon Exp $
+\versionid $Id: faq.but,v 1.54 2004/02/04 18:39:14 jacob Exp $
\A{faq} PuTTY FAQ
This FAQ is published on the PuTTY web site, and also provided as an
appendix in the manual.
+\H{faq-intro} Introduction
+
+\S{faq-what} What is PuTTY?
+
+PuTTY is a client program for the SSH, Telnet and Rlogin network
+protocols.
+
+These protocols are all used to run a remote session on a computer,
+over a network. PuTTY implements the client end of that session: the
+end at which the session is displayed, rather than the end at which
+it runs.
+
+In really simple terms: you run PuTTY on a Windows machine, and tell
+it to connect to (for example) a Unix machine. PuTTY opens a window.
+Then, anything you type into that window is sent straight to the
+Unix machine, and everything the Unix machine sends back is
+displayed in the window. So you can work on the Unix machine as if
+you were sitting at its console, while actually sitting somewhere
+else.
+
\H{faq-support} Features supported in PuTTY
In general, if you want to know if PuTTY supports a particular
ones will not. Adding an option to turn host key checking off
completely is the wrong solution and we will not do it.
+If you have host keys available in the common \c{known_hosts} format,
+we have a script called
+\W{http://cvs.tartarus.org/putty/contrib/kh2reg.py}\c{kh2reg.py}
+to convert them to a Windows .REG file, which can be installed ahead of
+time by double-clicking or using \c{REGEDIT}.
+
\S{faq-server}{Question} Will you write an SSH server for the PuTTY
suite, to go with the client?
\S{faq-pscp-ascii}{Question} Can PSCP or PSFTP transfer files in
ASCII mode?
-Unfortunately not. This is a limitation of the file transfer
-protocols: the SCP and SFTP protocols have no notion of transferring
-a file in anything other than binary mode.
+Unfortunately not.
+
+Until recently, this was a limitation of the file transfer protocols:
+the SCP and SFTP protocols had no notion of transferring a file in
+anything other than binary mode. (This is still true of SCP.)
-SFTP is designed to be extensible, so it's possible that an
-extension might be proposed at some later date that implements ASCII
-transfer. But the PuTTY team can't do anything about it until that
-happens.
+The current draft protocol spec of SFTP proposes a means of
+implementing ASCII transfer. At some point PSCP/PSFTP may implement
+this proposal.
\H{faq-ports} Ports to other operating systems
It's currently being worked on. If you look at the nightly source
snapshots, you should find a \c{unix} subdirectory, which should
-build you Unix ports of Plink, PuTTY itself, and also \c{pterm} - an
-\cw{xterm}-type program which supports the same terminal emulation
-as PuTTY. We do not yet have Unix ports of PSCP, PSFTP, Pageant or
-PuTTYgen.
+build you Unix ports of Plink, PuTTY itself, PuTTYgen, PSCP, PSFTP,
+and also \c{pterm} - an \cw{xterm}-type program which supports the
+same terminal emulation as PuTTY. We do not yet have a Unix port of
+Pageant.
\S{faq-wince}{Question} Will there be a port to Windows CE or PocketPC?
\S{faq-incorrect-mac}{Question} Why do I see \q{Incorrect MAC
received on packet}?
-This is due to a bug in old SSH 2 servers distributed by
-\cw{ssh.com}. Version 2.3.0 and below of their SSH 2 server
+One possible cause of this that used to be common is a bug in old
+SSH 2 servers distributed by \cw{ssh.com}. (This is not the only
+possible cause; see \k{errors-crc} in the documentation.)
+Version 2.3.0 and below of their SSH 2 server
constructs Message Authentication Codes in the wrong way, and
expects the client to construct them in the same wrong way. PuTTY
constructs the MACs correctly by default, and hence these old