<H2 align="center">Frequently Asked Questions</H2>
-<!--#include virtual="faqbody.html" -->
+<table><tr valign=top><td><ul>
+<li><a href="#1">the transfer fails to finish</a><br>
+<li><a href="#2">copies every file</a><br>
+<li><a href="#3">is your shell clean</a><br>
+<li><a href="#4">memory usage</a><br>
+<li><a href="#5">out of memory</a><br>
+<li><a href="#6">rsync through a firewall</a><br>
+</ul></td><td> </td><td><ul>
+<li><a href="#7">rsync and cron</a><br>
+<li><a href="#8">rsync: Command not found</a><br>
+<li><a href="#9">spaces in filenames</a><br>
+<li><a href="#10">ignore "vanished files" warning</a><br>
+<li><a href="#11">read-only file system</a><br>
+</ul></td></tr></table>
+
+<hr>
+<h3><a name=1>the transfer fails to finish</a></h3>
+
+<p>If you get an error like one of these:
+
+<pre>rsync: error writing 4 unbuffered bytes - exiting: Broken pipe
+rsync error: error in rsync protocol data stream (code 12) at io.c(463)
+</pre>
+
+<p>or
+
+<pre>rsync: connection unexpectedly closed (24 bytes read so far)
+rsync error: error in rsync protocol data stream (code 12) at io.c(342)
+</pre>
+
+<p>please read the <a href="issues.html">issues and debugging page</a>
+for details on how you can try to figure out what is going wrong.
+
+<hr>
+<h3><a name=2>copies every file</a></h3>
+
+<p>Some people occasionally report that rsync copies every file when they
+expect it to copy only a small subset. In most cases the explanation is
+that you forgot to include the --times (-t) option in the original copy,
+so rsync is forced to (efficiently) transfer every file to see if it has
+changed (because the modified time and size do not match).
+
+<p>Another common cause involves sending files to an Microsoft filesystem:
+if the file's modified time is an odd value but the receiving filesystem
+can only even values, then rsync will re-transfer too many files. You can
+avoid this by specifying the --modify-window=1 option.
+
+<p>If you think that rsync is erroneously copying every file then look at
+the stats produced with -v and see if rsync is really sending all the data.
+See also the --checksum (-c) option for one way to avoid the extra copying
+without synchronizing the modified times.
+
+<hr>
+<h3><a name=3>is your shell clean</a></h3>
+
+<p>The "is your shell clean" message and the "protocol mismatch" message
+are usually caused by having some sort of program in your .cshrc, .profile,
+.bashrc or equivalent file that writes a message every time you connect
+using a remote-shell program (such as ssh or rsh). Data written in this
+way corrupts the rsync data stream. rsync detects this at startup and
+produces those error messages. However, if you are using rsync-daemon
+syntax (host::path or rsync://) without using a remote-shell program (no
+--rsh or -e option), there is not remote-shell program involved, and the
+problem is probably caused by an error on the daemon side (so check the
+daemon logs).
+
+<p>A good way to test if your remote-shell connection is clean is to try
+something like this (use ssh or rsh, as appropriate):
+
+<blockquote><pre>ssh remotesystem /bin/true > test.dat</pre></blockquote>
+
+<p>That should create a file called test.dat with nothing in it. If
+test.dat is not of zero length then your shell is not clean. Look at the
+contents of test.dat to see what was sent. Look at all the startup files on
+remotesystem to try and find the problem.
+
+<hr>
+<h3><a name=4>memory usage</a></h3>
+
+<p>Yes, rsync uses a lot of memory. The majority of the memory is used to
+hold the list of files being transferred. This takes about 100 bytes per
+file, so if you are transferring 800,000 files then rsync will consume
+about 80M of memory. It will be higher if you use -H or --delete.
+
+<p>To fix this requires a major rewrite of rsync, which my or may not
+happen.
+
+<hr>
+<h3><a name=5>out of memory</a></h3>
+
+<p>The usual reason for "out of memory" when running rsync is that you are
+transferring a _very_ large number of files. The size of the files doesn't
+matter, only the total number of files.
+
+<p>As a rule of thumb you should expect rsync to consume about 100 bytes
+per file in the file list. This happens because rsync builds a internal
+file list structure containing all the vital details of each file. rsync
+needs to hold structure in memory because it is being constantly traversed.
+
+<p>A future version of rsync could be built with an improved protocol that
+transfers files in a more incremental fashion, which would require a lot
+less memory. Unfortunately, such an rsync does not yet exist.
+
+<hr>
+<h3><a name=6>rsync through a firewall</a></h3>
+
+<p>If you have a setup where there is no way to directly connect two
+systems for an rsync transfer, there are several ways to get a firewall
+system to act as an intermediary in the transfer. You'll find full details
+on the <a href="firewall.html">firewall methods</a> page.
+
+<hr>
+<h3><a name=7>rsync and cron</a></h3>
+
+<p>On some systems (notably SunOS4) cron supplies what looks like a socket
+to rsync, so rsync thinks that stdin is a socket. This means that if you
+start rsync with the --daemon switch from a cron job you end up rsync
+thinking it has been started from inetd. The fix is simple—just
+redirect stdin from /dev/null in your cron job.
+
+<hr>
+<h3><a name=8>rsync: Command not found</a></h3>
+
+<p>This error is produced when the remote shell is unable to locate the rsync
+binary in your path. There are 3 possible solutions:
+
+<ol>
+
+<li>install rsync in a "standard" location that is in your remote path.
+
+<li>modify your .cshrc, .bashrc etc on the remote system to include the path
+that rsync is in
+
+<li>use the --rsync-path option to explicitly specify the path on the
+remote system where rsync is installed
+
+</ol>
+
+<p>You may echo find the command:
+
+<blockquote><pre>ssh host 'echo $PATH'</pre></blockquote>
+
+<p>for determining what your remote path is.
+
+<hr>
+<h3><a name=9>spaces in filenames</a></h3>
+
+<p>Can rsync copy files with spaces in them?
+
+<p>Short answer: Yes, rsync can handle filenames with spaces.
+
+<p>Long answer:
+
+<p>Rsync handles spaces just like any other unix command line application.
+Within the code spaces are treated just like any other character so a
+filename with a space is no different from a filename with any other
+character in it.
+
+<p>The problem of spaces is in the argv processing done to interpret the
+command line. As with any other unix application you have to escape spaces
+in some way on the command line or they will be used to separate arguments.
+
+<p>It is slightly trickier in rsync (and other remote-copy programs like
+scp) because rsync sends a command line to the remote system to launch the
+peer copy of rsync (this assumes that we're not talking about daemon mode,
+which is not affected by this problem because no remote shell is involved
+in the reception of the filenames). The command line is interpreted by the
+remote shell and thus the spaces need to arrive on the remote system
+escaped so that the shell doesn't split such filenames into multiple
+arguments.
+
+<p>For example:
+
+<blockquote><pre>rsync -av host:'a long filename' /tmp/</pre></blockquote>
+
+<p>This is usually a request for rsync to copy 3 files from the remote
+system, "a", "long", and "filename" (the only exception to this is for a
+system running a shell that does not word-split arguments in its commands,
+and that is exceedingly rare). If you wanted to request a single file with
+spaces, you need to get some kind of space-quoting characters to the remote
+shell that is running the remote rsync command. The following commands
+should all work:
+
+<blockquote><pre>rsync -av host:'"a long filename"' /tmp/
+rsync -av host:'a\ long\ filename' /tmp/
+rsync -av host:a\\\ long\\\ filename /tmp/</pre></blockquote>
+
+<p>You might also like to use a '?' in place of a space as long as there
+are no other matching filenames than the one with spaces (since '?' matches
+any character):
+
+<blockquote><pre>rsync -av host:a?long?filename /tmp/</pre></blockquote>
+
+<p>As long as you know that the remote filenames on the command line
+are interpreted by the remote shell then it all works fine.
+
+<hr>
+<h3><a name=10>ignore "vanished files" warning</a></h3>
+
+<p>Some folks would like to ignore the "vanished files" warning, which
+manifests as an exit-code 24. The easiest way to do this is to create
+a shell script wrapper. For instance, name this something like
+"rsync-no24":
+
+<blockquote><pre>#!/bin/sh
+rsync "$@"
+e=$?
+if test $e = 24; then
+ exit 0
+fi
+exit $e</pre></blockquote>
+
+<hr>
+<h3><a name=11>read-only file system</a></h3>
+
+<p>If you get "Read-only file system" as an error when sending to a rsync
+daemon then you probably forgot to set "read only = no" for that module.
+
+<hr>
+
+
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