kdirstat/doc/en/index.docbook

<?xml version="1.0" ?>
<!DOCTYPE book PUBLIC "-//KDE//DTD DocBook XML V4.1-Based Variant V1.0//EN" "dtd/kdex.dtd" [
  <!ENTITY kdirstat '<application>KDirStat</application>'>
  <!ENTITY kapp "&kdirstat;"><!-- replace |NAMELITTLE| here -->
  <!ENTITY % addindex "IGNORE">
  <!ENTITY % English "INCLUDE"><!-- change language only here -->


  <!-- Do not define any other entities; instead, use the entities
       from kde-genent.entities and $LANG/user.entities. -->
]>
<!-- kdoctemplate v0.8 October 1 1999
     Minor update to "Credits and Licenses" section on August 24, 2000
     Removed "Revision history" section on 22 January 2001   -->

<!--
This template was designed by: David Rugge davidrugge@mindspring.com
with lots of help from: Eric Bischoff ebisch@cybercable.tm.fr
and Frederik Fouvry fouvry@sfs.nphil.uni-tuebingen.de
of the KDE DocBook team.

You may freely use this template for writing any sort of KDE documentation.
If you have any changes or improvements, please let us know.

In the future, we may want to change from SGML-based DocBook to XML-based
DocBook. To make this change easier, please be careful :
- in XML, the case of the <tags> and attributes is relevant ;
- also, quote all attributes.

Please don't forget to remove all these comments in your final documentation,
thanks ;-).
-->

<!-- ................................................................ -->

<!-- The language must NOT be changed here. -->

<book lang="&language;">

<!-- This header contains all of the meta-information for the document such
as Authors, publish date, the abstract, and Keywords -->

<bookinfo>
<title>The KDirStat Handbook</title>

<authorgroup>
<author>
<firstname>Stefan</firstname>
<surname>Hundhammer</surname>
<affiliation>
<address><email>sh@suse.de</email></address>
</affiliation>
</author>
</authorgroup>

<!-- TRANS:ROLES_OF_TRANSLATORS -->

<copyright>
<year>1999-2005</year>
<holder>Stefan Hundhammer</holder>
</copyright>
<!-- Translators: put here the copyright notice of the translation -->
<!-- Put here the FDL notice.  Read the explanation in fdl-notice.docbook
     and in the FDL itself on how to use it. -->
<legalnotice>&FDLNotice;</legalnotice>

<!-- Date and version information of the documentation
Don't forget to include this last date and this last revision number, we
need them for translation coordination !
Please respect the format of the date (DD/MM/YYYY) and of the version
(V.MM.LL), it could be used by automation scripts.
Do NOT change these in the translation. -->

<date>02/02/2002</date>
<releaseinfo>0.1.01</releaseinfo>


<!-- Abstract about this handbook -->

<abstract>
<para>
&kdirstat; is a graphical disk usage utility, very much like the Unix "du" command,
plus some cleanup facilities to reclaim disk space.
</para>
</abstract>

<!-- This is a set of Keywords for indexing by search engines.
Please at least include KDE, the KDE package it is in, the name
 of your application, and a few relevant keywords. -->

<keywordset>
<keyword>KDE</keyword>
<keyword>tdeutils</keyword>
<keyword>utilities</keyword>
<keyword>file system</keyword>
<keyword>disk usage</keyword>
<keyword>cleanup</keyword>
</keywordset>

</bookinfo>

<!-- The contents of the documentation begin here.  Label
each chapter so with the id attribute. This is necessary for two reasons: it
allows you to easily reference the chapter from other chapters of your
document, and if there is no ID, the name of the generated HTML files will vary
from time to time making it hard to manage for maintainers and for the CVS
system. Any chapter labelled (OPTIONAL) may be left out at the author's
discretion. Other chapters should not be left out in order to maintain a
consistent documentation style across all KDE apps. -->




<chapter id="overview">
<title>Overview</title>

<!-- The introduction chapter contains a brief introduction for the
application that explains what it does and where to report
problems. Basically a long version of the abstract.  Don't include a
revision history. (see installation appendix comment) -->

<para>
&kapp; is a graphical disk usage utility. It shows you where all your disk
space has gone and tries to help clean it up.
</para>


<sect1 id="screenshot">
<title>Screen Shot</title>

<para>

<screenshot>
<screeninfo>The &kapp; main window</screeninfo>
	<mediaobject>
	  <imageobject>
	    <imagedata fileref="kdirstat-main.png" format="PNG"/>
	  </imageobject>
	  <textobject>
	    <phrase>Main window screenshot</phrase>
	  </textobject>
	</mediaobject>
</screenshot>
</para>
</sect1>




<sect1 id="features">
<title>Features</title>


<sect2><title>Display Features</title>
<itemizedlist>

<listitem><para>
Graphical and numeric display of used disk space
</para></listitem>

<listitem><para>
Treemap display of used disk space
</para></listitem>

<listitem><para>
Files kept apart from directories in separate &lt;Files&gt; items to prevent
cluttering the display
</para></listitem>


<listitem><para>
All numbers displayed human readable - e.g., 34.4 MB instead of 36116381 Bytes
</para></listitem>


<listitem><para>
Reasonable handling of sparse files - only blocks that are actually allocated
are added up to the total sums.
</para></listitem>


<listitem><para>
Reasonable handling of (regular) files with multiple hard links - their size is
divided by their number of hard links, thus evenly distributing their size over
the directories they are linked to -- and, more importantly, not adding the same
file up several times.
</para></listitem>


<listitem><para>
Different colors in the directory tree display to keep the different tree
levels visually apart
</para></listitem>


<listitem><para>
Display of latest change time within an entire directory tree - you can easily
see what object was changed last and when.
</para></listitem>

</itemizedlist>
</sect2>


<sect2><title>Directory Reading</title>
<itemizedlist>

<listitem>
<para>
Stays on one file system by default - reads mounted file systems only on
request.
</para>
<para>
You don't care about a mounted /usr file system if the root file
system is full and you need to find out why in a hurry, nor do you want to scan
everybody's home directory on the NFS server when your local disk is full.
</para>
</listitem>


<listitem><para>
Network transparency: Scan FTP or Samba directories - or whatever else
protocols KDE support.
</para></listitem>

<listitem><para>
PacMan animation while directories are being read.
OK, this is not exactly essential, but it's fun.
</para></listitem>


</itemizedlist>
</sect2>


<sect2><title>Cleaning up</title>
<itemizedlist>

<listitem><para>
Predefined cleanup actions: Easily delete a file or a directory tree, move it
to the KDE trash bin, compress it to a .tar.bz2 archive or simply open a shell
or a Konqueror window there.
</para></listitem>


<listitem><para>
User-defined cleanup actions: Add your own cleanup commands or edit the
existing ones.
</para></listitem>

<listitem><para>
"Send mail to owner" report facility: Send a mail requesting the owner
of a large directory tree to please clean up unused files.
</para></listitem>


</itemizedlist>
</sect2>


<sect2><title>Misc</title>
<itemizedlist>

<listitem><para>
Feedback mail facility: Rate the program and tell the authors your opinion
about it.
</para></listitem>

</itemizedlist>
</sect2>

</sect1>


<sect1 id="more-screen-shots">
<title>More Sceen Shots</title>


<sect2><title>Configuring cleanup actions</title>
<para>
<screenshot>
<screeninfo>Configuring cleanup actions</screeninfo>
	<mediaobject>
	  <imageobject>
	    <imagedata fileref="kdirstat-config-cleanups.png" format="PNG"/>
	  </imageobject>
	  <textobject>
	    <phrase>Configure cleanup actions window screenshot</phrase>
	  </textobject>
	</mediaobject>
</screenshot>
</para>
</sect2>


<sect2><title>Configuring tree colors</title>
<para>
<screenshot>
<screeninfo>Configuring tree colors</screeninfo>
	<mediaobject>
	  <imageobject>
	    <imagedata fileref="kdirstat-config-tree-colors.png" format="PNG"/>
	  </imageobject>
	  <textobject>
	    <phrase>Configure tree colors window screenshot</phrase>
	  </textobject>
	</mediaobject>
</screenshot>
</para>
</sect2>

<sect2><title>Feedback mail</title>
<para>
<screenshot>
<screeninfo>Feedback mail</screeninfo>
	<mediaobject>
	  <imageobject>
	    <imagedata fileref="feedback-mail.png" format="PNG"/>
	  </imageobject>
	  <textobject>
	    <phrase>Feedback mail window screenshot</phrase>
	  </textobject>
	</mediaobject>
</screenshot>
</para>
</sect2>

</sect1>
</chapter>




<chapter id="basic_usage">
<title>Basic Usage</title>

<sect1 id="invoking">
<title>Invoke &kdirstat;</title>

<para>
Start &kdirstat; from the KDE menu, right-click a directory in a
Konqueror window or type
<userinput>kdirstat</userinput> or
<userinput>kdirstat &lt;directory-name&gt;</userinput> in a shell
window or at KDE's <guibutton>Run command</guibutton> prompt
(<keycap>Alt-F2</keycap>).
</para>
</sect1>

<sect1 id="select_dir">
<title>Select a Directory</title>

<para>
&kdirstat; will prompt for a directory if you didn't specify one when starting
it. You can specify local directories as well as URLs of remote locations -
<userinput>kdirstat /usr/lib</userinput> works as well as
<userinput>kdirstat ftp:/ftp.myserver.org/pub</userinput>.
</para>
<para>
In any case, &kdirstat; will start reading that directory. That might take a
while, but you can work with the program during all that time.
</para>
</sect1>

<sect1 id="find_out_where">
<title>Find out what Uses up all the Disk Space</title>

<para>
Look at the "Subtree Total" column or wait until a subtree is finished reading
and look at the graphical percentage bar display to find out what directory
subtee takes up how much disk space. Use the open / close icons (plus and minus
signs or small arrows, depending on how you set up your KDE) or double-click an
item to open or close it.
</para>
<para>
Notice how files at any directory level are kept apart from subdirectories -
there is a separate &lt;Files&gt; entry for them. This way, you can easily tell
how much disk space the files are using up in relation to the subdirectories
and their respective files.
</para>
</sect1>

<sect1 id="do_something">
<title>Do Something about it</title>

<para>
Once you found out where all your disk space goes, do something about it - this
is probably why you are using this program in the first place. You have several
options:
</para>

<itemizedlist>
<listitem>
<para>
Go to a computer hardware store and buy a new hard disk.
This is probably not what you want. ;-)
</para>
</listitem>

<listitem>
<para>Tell the owner of that file or directory to please clean up.
You can use &kdirstat; for that: Mark that file or directory (i.e., left-click
on it) and select <guibutton>Send Mail to Owner</guibutton>
from the context menu (right-click), from the tool bar (the envelope icon) or
from the <guibutton>Report</guibutton> menu.
</para>
<para>
A precomposed message will open in your
<link linkend="mail_client">favourite mail client</link>.
You can edit that text before actually sending it. The recipient of
the mail is the user who owns the file or directory you marked - but of course
you can edit that, too in the mail client.
</para>
<para>
The mail will contain those items that are currently displayed open from the
marked item on. If you want to include more items, open the respective
directories; if you want less, close them. Of course you can always delete
lines in the mail client if you find them irrelevant - there is no use
complaining about some 367 byte files along with others that take several
megabytes.
</para>

</listitem>

<listitem>
<para>
Invoke a "cleanup" action. There are several predefined ones, and you can
define your own. Use the context menu, the tool bar or the <guibutton>Clean
Up</guibutton> menu to find out which are available.
</para>
<para>
For some cleanup actions you will have to wait until the directory
tree is completely read until you can activate them. If a cleanup action
doesn't get enabled even then, the type of item you selected is inappropriate
for that kind of action: Some actions can only performed on directories, while
others can only be performed on files. Only very few actions work for
&lt;Files&gt; pseudo entries since they don't have a real counterpart in the
file system.
</para>
</listitem>
</itemizedlist>

</sect1>

</chapter>


<chapter id="treemaps">
<title>Treemaps</title>


<sect1 id="treemap_intro">
<title>Quick Introduction to Treemaps</title>


<sect2 id="what_are_treemaps">
<title>What is it?</title>

<para>
The shaded rectangles you can see in the lower half of the &kdirstat; main
window are called a "treemap". This is just another way of displaying items in
a tree that each have a numerical value, such as a file size.
</para>

<para>
Each rectangle corresponds to a file or directory on your hard disk. The larger
the rectangle (or, rather, the larger its area), the larger the file.
</para>

</sect2>



<sect2 id="how_to_use_treemaps">
<title>How to Use Treemaps</title>

<para>
Look at the largest rectangles. Click on one, and it is selected - both in
the treemap view and above in the tree view (the list above). You can now see
what file or directory that is - both in the tree view above and in the status
line below.
</para>

<para>
Find the largest rectangles, identify them, ant decide what to do with them:
Keep them, delete them, whatever. Use the cleanup actions like in the tree
view. The right mouse button opens a context menu that contains cleanup actions.
</para>

<para>
The shading gives hints about which files belong together in directories. The
bright spots indicate about where the center of parent directories is.
</para>

</sect2>



<sect2 id="treemap_advantages">
<title>Pros and Cons of Treemaps</title>

<para>
Treemaps are good for finding single large files, possibly very deeply nested
in the directory hierarchy. They don't help very much if lots of small files
clutter up a directory - use the tree view (the list) above the treemap for
that.
</para>

<para>
The treemap by itself view doesn't give away very much information other than
relative file sizes. It can tell you where large files are, even if they are
very deeply hidden in subdirectories. You always see all files at once, not
only the relative sizes of subdirectories against each other like in the tree
view. Click on a file to see more details in the tree view above.
</para>

<para>
Bottom line: Both the treemap and the tree view have their strenghs and
weaknesses. Use a combination of both to make best use of either's benefits.
</para>

</sect2>



<sect2 id="getting_rid_of_treemaps">
<title>How to Get Rid of it</title>

<para>
If you need the screen space for the tree view (the list) or if you find it
takes too long to update the tree view each time you delete a file, you can
drag the splitter between the tree view and the treemap all the way down. The
treemap doesn't get rebuilt below a certain minimum size, thus it doesn't eat
performance any more. Alternatively, uncheck "show treemap" in the "treemap"
menu or simply hit <keycap>F9</keycap>.
</para>

</sect2>
</sect1>



<sect1 id="treemap_actions">
<title>Treemap Related Actions</title>


<sect2 id="treemap_mouse_actions">
<title>Mouse Actions in the Treemap</title>

<itemizedlist>

<listitem><para>
A single click with the left mouse button selects the clicked file or directory
both in the treemap and in the tree view.
</para></listitem>

<listitem><para>
A single click with the middle mouse button selects the parent of the clicked
file or directory.
</para></listitem>

<listitem><para>
A single click with the right mouse button opens the context menu.
</para></listitem>

<listitem><para>
A double click with the left mouse button zooms the treemap in at the clicked
file or directory: The treemap is redisplayed with the near-topmost ancestor of
the clicked file or directory as the root.
</para></listitem>

<listitem><para>
A double click with the middle mouse button zooms out after zooming in.
</para>
<para>
If the treemap is not zoomed in at all, it is simply rebuilt to fit into the
available screen space without the need for scrollbars. This is mainly useful
if automatic treemap resizing (the default) is switched off.
</para></listitem>

<listitem><para>
Dragging the splitter above the treemap not only resizes the treemap subwindow,
it also rebuilds the treemap and makes it fit into the available space.
</para></listitem>

<listitem><para>
You can drag the splitter all the way down to deactivate the treemap
alltogether. Below a minimum size the treemap will not be updated any more, so
it doesn't cost any performance.
</para></listitem>

</itemizedlist>

</sect2>


<sect2 id="treemap_menu_actions">
<title>Treemap Menu Actions</title>

<para>
Most treemap mouse actions have counterparts in the "treemap" menu.
</para>

<para>
In addition to that, "show treemap" in the "treemap" menu toggles display of
the treemap subwindow. If disabled, the treemap is really inactive and doesn't
cost any performance.
</para>

</sect2>
</sect1>


<sect1 id="treemap_in_depth">
<title>More Information about Treemaps</title>

<sect2 id="simple_treemap_construction">
<title>How a Simple Treemap is Constructed</title>

<para>
In its most basic form, construction of a treemap is very easy:
</para>

<para>
First, you need a tree where each node has an associated value. Directory trees
with their accumulated file sizes are a very natural example. However, the tree
needs to be complete with all accumulated values before anything can be done -
that's why &kdirstat; doesn't display a treemap while directories are being
read.
</para>

<para>
Decide upon an direcion in which to split the available area initially. Since
normally the treemap subwindow is wider than it is high, we first split
horizontally.
</para>

<para>
Split the area so each toplevel directory gets an area proportional to its
accumulated size (i.e., its own size plus the size of all its children,
grandchildren etc.).
</para>

<para>
For each rectangle thus constructed, repeat the process for each directory
level, but change direction for each level. For example, the second level will
be split vertically, the third again horizontally etc.
</para>

<para>
This basic algorithm as well as the idea of treemaps at all was introduced by
Ben Shneiderman quite some years ago.
</para>

</sect2>



<sect2 id="squarified_treemaps">
<title>Squarified Treemaps</title>

<para>
One major drawback of the simple treemap algorithm is that it usually results
in lots of very thin, elongated rectangles that are hard to point at with the
mouse and hard to compare visually against each other. This is why &kdirstat;
uses "squarified" treemaps as described by Mark Bruls, Kees Huizing, and Jarke
J. van Wijk of the Technical University of Eindhoven in the Netherlands. The
basic idea is to improve the aspect ratio of the resulting rectangles, thus to
make them more "square-like". Even though this doesn't always work out
perfectly, it usually improves things a lot: There are normally very few (if
any) thin, elongated rectangles in such a squarified treemap.
</para>

</sect2>


<sect2 id="cushioned_treemaps">
<title>The Shading: Cushioned Treemaps</title>

<para>
Squarifying a treemap comes at a cost: It makes the structure of the underlying
tree even less obvious for the user. Where simple treemaps change direction for
each level of subdivision, sqarified treemaps change direction within each
level. The result are clusters of more or less square-like rectangles. The only
hint about the tree structure that is given is that larger rectangles are near
the left and at the top of each level.
</para>

<para>
Thus, &kdirstat; uses a technique described by Jarke J. van Wijk and Huub van
de Wetering of the TU Eindhoven, NL: "Cushioned" treemaps. This is the 3D-like
shading you can see in &kdirstat;'s treemaps: It gives each rectangle within
the treemap (each "tile") a cushion-like impression. This is not just for
pretty looks, its main purpose is to group files optically together.
</para>

</sect2>


<sect2 id="treemaps_optimizations">
<title>&kdirstat;'s own Treemap Improvements</title>

<para>
The squarification algorithm requires items to be sorted by size. A Linux/Unix
directory tree, however, usually has lots of items; a full-blown Linux
installation can easily consist of 150,000+ (!) files and directories. The best
sort algorithms (heap sort, quick sort) still have a cost in the order of
n*ln(n), i.e. they are proportional to the product of the number of items times
their logarithm.
</para>

<para>
Likewise, the cushion shading algorithm requires relatively expensive
floating-point arithmetics for each individual pixel of each treemap tile (even
though, by the way, it is very efficient for a 3D-shading algorithm - no
expensive sinus/cosinus etc. calculation required).
</para>

<para>
On the other hand, most items in large directory trees are so tiny they cannot
be seen at all. &kdirstat; simply omits everything that will result in treemap
tiles less than a predefined (3*3 pixels) size - they are pretty useless for
the purposes of &kdirstat;'s users anyway. Those tiny thingies may end up in
some featureless grey space in the treemap display.
</para>

<para>
So don't wonder if you click on some grey pixels and &kdirstat; insists they
belong to a rather high-level directory: &kdirstat; simply means to tell you
that those pixels correspond to some small stuff in that directory. Use the
tree view (the list) above the treemap for more detailed information.
</para>

</sect2>

<sect2 id="treemaps_credits">
<title>Credits and Further Reading about Treemaps</title>

<itemizedlist>

<listitem><para>
SequoiaView gave the inspiration for treemaps within &kdirstat;. SequoiaView is
a MS Windows (that's the bad part) program created at the TU Eindhoven, NL. It
introduced cushion treemaps and later squarified cushion treemaps. Its purpose
is very close to &kdirstat;'s. If you are looking for a &kdirstat;-like program
on that "other" ;-) platform, go for SequoiaView:

<ulink url="http://www.win.tue.nl/sequoiaview">
http://www.win.tue.nl/sequoiaview
</ulink>.

</para>
<para>
Needless to say, &kdirstat; users should easily be able to simply mount their
MS Windows partitions and use &kdirstat; to clean up those as well. The only
acceptable excuse ;-) for not doing this might be NTFS partitions (no reliable
write access from Linux to those yet) or single-OS MS Windows machines.
</para></listitem>

<listitem><para>
Ben Shneiderman invented treemaps - a truly intuitive way of visualizing
numerical contents of a tree. For more information, see

<ulink url="http://www.cs.umd.edu/hcil/treemaps/">
http://www.cs.umd.edu/hcil/treemaps/
</ulink>.
</para></listitem>

<listitem><para>
Jarke J. van Wijk and Huub van de Wetering from the TU Eindhoven, NL wrote a
paper called "Cushion Treemaps: Visualization of Hierarchical Information". It
is available in PDF format at

<ulink url="http://www.win.tue.nl/~vanwijk/">
http://www.win.tue.nl/~vanwijk/
</ulink>.
</para></listitem>

<listitem><para>
Mark Bruls, Kees Huizing and Jarke J. van Wijk from the TU Eindhoven wrote a
paper called "Squarified Treemaps". It is also available in PDF format at
<ulink url="http://www.win.tue.nl/~vanwijk/">
http://www.win.tue.nl/~vanwijk/
</ulink>.
</para></listitem>

<listitem><para>
Alexander Rawass had written a previous implementation of treemaps for
&kdirstat;. Even that part has been completely replaced for various reasons
(performance, integration into the &kdirstat; main application, memory
consumption, stability, user interface conformance, lack of maintenance), it
had proven that treemaps are a useful addition for a program like &kdirstat;.
</para></listitem>

<listitem><para>
Frederic Vernier and Laurence Nigay from the University of Grenoble, France
wrote a paper called "Modifiable Treemaps Containing Variable-Shaped Units"
(URL unknown, sorry). They also wrote a MS Windows programm called "parent"
that uses a mixture of treemaps and file lists within individual treemap
tiles.
</para><para>
Personally, I don't like that approach very much - I find that display very
cluttered and confusing (that is why I didn't adopt anything like that for
&kdirstat;). But this is just my personal opinion that others may or may not
share.
</para></listitem>

</itemizedlist>

</sect2>
</sect1>
</chapter>



<chapter id="predefined_cleanups">
<title>Predefined Cleanup Actions</title>

<para>
&kdirstat; comes with a number of predefined cleanup actions. You can configure
them all to your personal preference, and you can add your own. Here is what
the predefined cleanup actions do:
</para>

<sect1 id="cleanup_open_in_konqueror">
<title>Open in Konqueror</title>

<para>
This opens the selected item in a Konqueror window.
</para>
<para>
You can use Konqueror to delete it (but then, you can also do that more easily
from within &kdirstat;), you can move it to another place or you can examine it
more closely.
</para>
<para>
If the selected item is a known MIME type, this will open the appropriate
application. For example, if you invoke
<guibutton>Open in Konqueror</guibutton> on a PNG image, Konqueror will
immediately start an image viewer and display that image.
</para>
<para>
This is the Swiss army knife of cleanup actions: You can do a lot of different
things with it. Thus, &kdirstat; cannot know if and when it makes sense to
re-read that directory - you will have to do that manually:
Select <guibutton>Refresh selected</guibutton> from the context menu
(right-click) or from the <guibutton>File</guibutton> menu.
</para>
</sect1>


<sect1 id="cleanup_open_in_terminal">
<title>Open in Terminal</title>

<para>
This opens a terminal window in the directory of the selected item.
</para>

<para>
Use this to issue a few shell commands in that directory, then simply close
that shell window. You can easily open a new one in a different directory if
you need one, so you might want not to bother to repeatedly type
<userinput>cd</userinput> with lenghty paths - simply close that shell and open
a new one at the new location (type <keycap>Ctrl</keycap>-<keysym>T</keysym>.
</para>
<para>
As with the <guibutton>Open in Konqueror</guibutton> cleanup action described
above, you must manually re-read the directory's contents if you make
changes. Otherwise they will not be reflected in &kdirstat;'s display.
</para>
</sect1>


<sect1 id="cleanup_compress">
<title>Compress</title>

<para>
This compresses the selected directory to a .tar.bz2 archive.
</para>

<para>
For example, a subdirectory
<userinput>/work/home/kilroy/loveletters</userinput> will become a compressed
archive <userinput>/work/home/kilroy/loveletters.tar.bz2</userinput>.
The directory is removed once the compressed archive is successfully created
(but of course not if that failed).
</para>
<para>
Any existing archive of the same name will silently be overwritten.
</para>
<para>
Remember that Konqueror and related utilities can use that kind of archive
transparently; there is no need to unpack it if you want to read a file in that
archive. Simply click into the archive in Konqueror.
</para>

<para>
If you prefer .tgz archives to .tar.bz2, change the command line in the
<link linkend="configuring_cleanups">cleanup settings</link>. With .tar.bz2,
this is
</para>
<para>
<userinput>
cd ..; tar cjvf &percnt;n.tar.bz2 &percnt;n &amp;&amp; rm -rf &percnt;n
</userinput>
</para>
<para>
For .tgz archives, change this to
</para>
<para>
<userinput>
cd ..; tar czvf &percnt;n.tgz &percnt;n &amp;&amp; rm -rf &percnt;n
</userinput>
</para>
<para>
But you might think twice before doing that: "bzip2" (for .tar.bz2) compresses
a lot more efficient than ordinary "gzip" (for .tgz or .tar.gz), and most
systems support that just as well. It's just a matter of getting used to typing
<userinput>tar cjvf</userinput> rather than <userinput>tar czvf</userinput> for
creating an archive or <userinput>tar xjvf</userinput> rather than <userinput>tar
xzvf</userinput> for unpacking it.
</para>

</sect1>


<sect1 id="cleanup_make_clean">
<title>make clean</title>

<para>
This issues a <userinput>make clean</userinput> command in the selected
directory.
</para>
<para>
This is useful if you build software from source frequently. After successfully
installing the software (<userinput>make install</userinput>), there is no
need to keep the built binaries around in the source directory any longer. On
the other hand, people frequently forget to clean up those directories, so you
can do that from within &kdirstat; with a few mouse clicks.
</para>
</sect1>


<sect1 id="cleanup_clean_trash">
<title>Delete Trash Files</title>

<para>
This deletes files that are usually superfluous, such as editor backup files or
core dumps in the selected directory and in any of its subdirectories.
</para>
<para>
By default, the following types of files are deleted:
</para>
<itemizedlist>
<listitem><para>Object files left over from compiling software: *.o</para></listitem>
<listitem><para>Editor backup files: *~ *.bak *.auto</para></listitem>
<listitem><para>Core dump files: core</para></listitem>
</itemizedlist>

<para>
Of course, you can <link linkend="configuring_cleanups">configure this</link>
to suit your personal preferences.
</para>

</sect1>


<sect1 id="cleanup_delete_to_trash_bin">
<title>Delete (to Trash Bin)</title>

<para>
This invokes the KDE standard "delete" operation, i.e. the selected file or
directory is moved to the KDE trash bin.
</para>
<para>
Even though this doesn't help to reclaim disk space right away, it is a safe
method of deleting. Use this action for anything you want to get rid of and
then review your actions by looking into the KDE trash bin. If you are really
sure, select <guibutton>Empty Trash Bin</guibutton> there. Until that point,
you can always move those items back to where they came from.
</para>
<para>
You might consider not using this cleanup action if you are cleaning up a
directory on a different file system than your home directory: In that case
that "moving to trash" involves copying the items (and then deleting them at
the original location) which might take a while.
</para>
<para>
Notice that when moving an item to trash is not successful, &kdirstat; will
still falsely display that item as deleted even though it's still there. Use
<guibutton>Refresh selected</guibutton> from the context menu to update the
display manually. Read <link linkend="assume_deleted">here</link> why.
</para>
</sect1>


<sect1 id="cleanup_hard_delete">
<title>Delete (no way to undelete!)</title>

<para>
This is a real delete, not simply moving something to the trash bin. It's
quicker, and disk space is reclaimed immediately, but there is no way to
recover if you made a mistake. You will be prompted for confirmation when you
invoke this.
</para>
<para>
You can <link linkend="confirmation">change the configuration to not prompt for
confirmation</link>, but don't blame me if anything goes wrong after you did that.
</para>
<para>
As with <guibutton>Delete (to Trash Bin)</guibutton>, you will need to manually
re-read a directory if this went wrong (usually due to insufficient permissions)
- &kdirstat;'s display is out of sync with the hard disk if that happens.
Read <link linkend="assume_deleted">here</link> why.
</para>
</sect1>


</chapter>

<chapter id="configuring_cleanups">
<title>Configuring Cleanup Actions</title>


<para>
Select <guibutton>Configure &kdirstat;...</guibutton> from the
<guibutton>Settings</guibutton> menu and switch to the
<guibutton>Cleanups</guibutton> page:
</para>

<para>
<screenshot>
<screeninfo>Configuring cleanup actions</screeninfo>
	<mediaobject>
	  <imageobject>
	    <imagedata fileref="kdirstat-config-cleanups.png" format="PNG"/>
	  </imageobject>
	  <textobject>
	    <phrase>Configure cleanup actions window screenshot</phrase>
	  </textobject>
	</mediaobject>
</screenshot>
</para>

<sect1 id="config_cleanups_reference">
<title>Reference</title>

<para>
Select the cleanup action you want to configure from the list at the left
side. You might need to check <guibutton>Enabled</guibutton> before you can
make any changes.
</para>

<para>
Enter a title in the <guibutton>Title</guibutton> field. You should mark one of
the characters in the title with an ampersand ('&amp;') to provide a keyboard
shortcut in the menus.
</para>

<para>
Enter a shell command in the <guibutton>Command line</guibutton> field. The
command will be invoked with <userinput>/bin/sh</userinput>, so you can use
everything the default shell provides - including pipelines, logical 'and' or
'or' ('&amp;&amp;' or '||', respectively) or multiple commands separated by
semicolons. Use '%p' for the full path (or URL) of the currently selected file
or directory or '%n' for the name without path. '%t' will be expanded to the
full path name of the KDE trash directory (usually ${HOME}/Desktop/Trash, but
since this tends to change between different KDE versions it is safer to use
'%t').
</para>
<para>
&kdirstat;
will always change directory to the selected item, so there is no need to
manually add a <userinput>cd</userinput> command to the command line.
</para>
<para>
Commands are started in the background if possible, so don't add an extra
ampersand '&amp;'.
</para>

<para>
Check <guibutton>Recurse into subdirectories</guibutton> if the command should
be called for each subdirectory of the selected directory. Whether or not this
is useful depends on the kind of command you entered: A <userinput>make
clean</userinput> command usually takes care of that internally, while it's a
lot easier to use <userinput>rm -f *.bak</userinput> and let &kdirstat; handle
subdirectories rather than using a more complex <userinput>find ... | xargs
...</userinput> command.
</para>

<para id="confirmation">
Check <guibutton>Ask for confirmation</guibutton> if you want to prompt the
user for confirmation every time he invokes that cleanup action (but not for
each recursive subdirectory!). But beware: Having to confirm a lot of such
prompts tends to make users unattentive. They begin to blindly confirm
everything out of habit. Thus, use confirmations only when really necessary.
</para>

<para>
Check the category of objects this cleanup action works for. Not all commands
make sense for both files and directories. &lt;Files&gt; pseudo entries are a
very special case: They don't have a real counterpart on the hard disk. You can
safely check the &lt;Files&gt; category for actions that require changing
directory to somewhere and then execute a command there, but there is no use
trying to delete such a &lt;Files&gt; entry.
</para>

<para>
Choose between <guibutton>On local machine only ('file:/' protocol)</guibutton>
and <guibutton>Network transparent (ftp, smb, tar, ...)</guibutton>.
Most commands run locally only. There are only a few exceptions: For example,
you can open a remote location in many KDE applications, e.g., Konqueror.
</para>

<para>
Select a <guibutton>Refresh Policy</guibutton> to tell &kdirstat; how to update
its display after the cleanup action has been invoked:
</para>

<itemizedlist>

<listitem>
<para>
<guibutton>No refresh</guibutton>: Don't refresh the display. Either the
cleanup action doesn't change the directory tree anyway or it is unknown when
or how - or you don't care.
</para>
<para>
Cleanup actions with this refresh policy are the only ones that can be invoked
while the respective directory subtree is being read. All others can only be
started once reading is finished.
</para>
</listitem>

<listitem>
<para>
<guibutton>Refresh this entry</guibutton>: Refresh the directory branch the
cleanup action was selected with. This is the most useful refresh policy for
cleanup actions that delete a number of items from a directory tree, for
example <guibutton>Delete Trash Files</guibutton>.
</para>
<para>
If this refresh policy is selected, the command is not started in the
background: &kdirstat; has to wait for it to finish so the directory display
can be refreshed at the proper time.
</para>
</listitem>

<listitem>
<para>
<guibutton>Refresh this entry's parent</guibutton>: Similar to
<guibutton>Refresh this entry</guibutton>, but one level higher up. Useful for
cleanup actions that delete the selected item but create a new one on the same
level, for example the <guibutton>Compress</guibutton> standard cleanup: The
original directory is deleted, but a .tar.bz2 file is created instead.
</para>
<para>
If this refresh policy is selected, the command is not started in the
background: &kdirstat; has to wait for it to finish so the directory display
can be refreshed at the proper time.
</para>
</listitem>

<listitem>
<para id="assume_deleted">
<guibutton>Asume entry has been deleted</guibutton>: Don't really re-read
anything from disk, but assume the cleanup action deletes the selected
item, thus simply remove that item from the directory tree's representation in
&kdirstat;'s internal data structures.
</para>
<para>
This is much faster than any real refresh, but it might cause the internal data
structures to get out of sync with the hard disk if the cleanup action fails and
doesn't really delete the selected item. In this case, the user will have to
manually re-read that directory branch.
</para>
</listitem>
</itemizedlist>


</sect1>

<sect1 id="config_cleanups_example">
<title>Examples</title>

<sect2>
<title>Open in Emacs</title>

<para>
This is a trivial example that shows you how to add a new cleanup action that
opens a file in Emacs (or any other editor of your choice).
</para>

<para>
Select one of the unused user-defined cleanup actions from the list. Make sure
<guibutton>Enabled</guibutton> is checked.
</para>

<para>
Enter <userinput>Open in &amp;Emacs</userinput> in the
<guibutton>Title</guibutton> field. Notice the '&amp;': This marks the letter
'E' as this cleanup action's keyboard shortcut.
</para>

<para>
Enter <userinput>emacs &percnt;p</userinput> in the <guibutton>Command
line</guibutton> field.
</para>

<para>
Leave both <guibutton>Recurse into subdirectories</guibutton> and
<guibutton>Ask for confirmation</guibutton> unchecked.
</para>

<para>
Make sure only <guibutton>Files</guibutton> is checked in the <guibutton>Works
for...</guibutton> section and <guibutton>Directories</guibutton> and
<guibutton>&lt;Files&gt; pseudo entries</guibutton> are unchecked. If you like
Emacs' "dired" mode very much, you can also leave
<guibutton>Directories</guibutton> checked, but it definitely doesn't make any
sense trying to open an editor with a &lt;Files&gt; entry.
</para>

<para>
Leave <guibutton>On local machine only</guibutton> selected. If you feel like
experimenting a lot, you can try setting up Emacs so it fetches files from
remote locations, but even then most likely only the 'ftp' protocol will work.
</para>

<para>
Leave the <guibutton>Refresh Policy</guibutton> at
<guibutton>No refresh</guibutton>. This ensures Emacs is started
in the background and you can continue working with &kdirstat; while Emacs
runs. It wouldn't make too much sense to change the command line to
<userinput>emacs &percnt;p &amp;</userinput> and change the refresh policy to, say,
<guibutton>Refresh this entry</guibutton>: The refresh would take place
immediately after Emacs starts, and this is probably not what you want.
</para>


</sect2>

<sect2>
<title>Compress</title>

<para>
This example explains the predefined <guibutton>Compress</guibutton> cleanup
action in more detail. Remember, this cleanup action makes a compressed
.tar.bz2 archive from a directory.
</para>

<para>
The <guibutton>Command line</guibutton> for this cleanup action is:
</para>

<para>
<userinput>
cd ..; tar cjvf &percnt;n.tar.bz2 &percnt;n &amp;&amp; rm -rf &percnt;n
</userinput>
</para>

<para>
<userinput>cd ..</userinput> changes directory one level up. We don't
want to do something in the selected directory, but one level higher.
</para>

<para>
The semicolon <userinput>;</userinput> tells the shell to execute one more
command - unconditionally, no matter if the previous command succeeded or
failed.
</para>

<para>
<userinput>tar cjvf &percnt;n.tar.bz2 &percnt;n &amp;&amp;</userinput>
is where the compressed .tar.bz2 archive is created. "c" is the tar command for
"create", "j" means "use bzip2 compression", "v" is "verbose" (even though this
is strictly spoken unnecessary here), "f" means use the next argument as the
target file name rather than some default tape device (which nowadays nobody
uses any more anyway). "&percnt;n.tar.bz2" will be expanded to the name of the
selected directory without path plus "tar.bz2", "&percnt;n" will be expanded to
the name without anything else. For a directory
<userinput>/usr/lib/something</userinput> all this will result in a command
</para>
<para>
<userinput>tar cjvf something.tar.bz2 something</userinput>
</para>

<para>
<userinput>&amp;&amp;</userinput> makes the shell execute the rest only if the
previous command (the <userinput>tar</userinput> command) is executed
successfully. This is used here to make sure the directory only is deleted if
we really have a .tar.bz2 archive with the same contents so we can easily
restore it when necessary. This is crucial in case there insufficient disk
space to create the archive or should we have insufficient permissions to
create the archive.
</para>

<para>
<userinput>rm -rf &percnt;n</userinput> recursively deletes the directory
without asking or complaining.
</para>

<para>
<guibutton>Works for...</guibutton> is enabled for directories only. Note it
wouldn't be a good idea to enable it for &lt;Files&gt; entries, too: The user
would rightfully expect the .tar.bz2 archive to contain the contents of the
&lt;Files&gt; entry only, i.e. only the files on that directory level. The
command would, however, pack the entire directory tree from the parent level on
into the .tar.bz2 file.
</para>

<para>
The <guibutton>Refresh Policy</guibutton> is set to
<guibutton>Refresh this entry's parent</guibutton> since not only the selected
item is changed, but its parent also: It loses one child (the directory) but
gets another one (the .tar.bz2 archive).
</para>

<para>
Please note that <guibutton>Recurse into subdirectories</guibutton> is not
checked here: the <userinput>tar</userinput> command and <userinput>rm
-rf</userinput> take care of any subdirectories.
</para>


</sect2>

</sect1>

</chapter>


<chapter id="feedback_mail">
<title>Feedback Mail</title>

<sect1 id="feedback_mail_description">
<title>Description</title>

<para>
<guibutton>Send Feedback Mail...</guibutton> from the
<guibutton>Help</guibutton> menu opens this dialog:
</para>

<para>
<screenshot>
<screeninfo>Feedback mail</screeninfo>
	<mediaobject>
	  <imageobject>
	    <imagedata fileref="feedback-mail.png" format="PNG"/>
	  </imageobject>
	  <textobject>
	    <phrase>Feedback mail window screenshot</phrase>
	  </textobject>
	</mediaobject>
</screenshot>
</para>

<para>
You answer the questions (at least those marked as required) and add your personal
comments (in English, if you can, or in the special case of &kdirstat;
alternatively in German).
</para>

<para>
Upon clicking on the <guibutton>Mail this...</guibutton> button, your
<link linkend="mail_client">mail client</link> opens with a
<link linkend="mail_example">precomposed mail</link>.
You can review that mail to make sure it doesn't contain anything you
don't like. When you are convinced the mail is okay and doesn't contain
anything you don't like, send it.
</para>

<para>
With your opinion and your personal comments, you can make a contribution to
the Open Source movement - even if you are not a developer, even if you don't
have a clue how to improve or change the software. Your opinion is important,
even if you decide you don't like the program and send the mail off with "this
program is crap" checked.
</para>

<para>
Open Source softare lives and breathes with user feedback. If you miss a
feature, tell us about it. If you consider an existing feature confusing, tell
us about it. If you find an application overloaded with features so you can't
find the ones you really need, tell us about it.
</para>

<para>
On the other hand, if you like the program the way it is and you wouldn't like
to see it changed in any way, tell us about that, too. If you simply want to
thank those who go through the trouble writing all that software, do it. Your
input is appreciated, be it positive or negative.
</para>

<para>
There is nothing more frustrating for an Open Source software author than that
lingering uncertainty if there is anybody out there who actually uses his
program. He may not get any response from users - does that mean nobody
uses the software, or does it mean it simply runs so good nobody has reason to
complain? You can contribute by telling him he is doing all right and he should
keep up the good work.
</para>

<para>
In the opposite case, why not tell the author of a particular annoying program
just how annoying it is? This may shake him sober and make him reconsider his
work.
</para>

<para>
Open Source is one of the world's greatest democracies. Make your vote!
</para>

</sect1>



<sect1 id="privacy">
<title>Privacy</title>

<para>
Your mail sent with <guibutton>Send Feedback Mail...</guibutton> is sent to the
authors of this program, to nobody else. No company or government institution
will get your mail address or any personal data. You might have noticed no
personal data are requested in the feedback form. In particular, you will never
receive spam e-mail of any kind because of sending feedback mail.
</para>

<para>
We, the authors of this program, loathe spam probably even more than the
average KDE user since we get so much of it - spam robots tend to extract
e-mail addresses from source code and from web pages, so you can be sure we do
our best to make life as hard as we can on the spammers and certainly not help
them in any way.
</para>

<para>
The purpose of all this feedback mail is to gather information about average
user satisfaction, about average opinions about an application's feature set,
an application's stability and learning curve. It's all about averages, thus no
specific user's data will ever be made available to the public - only
statistical averages over a large number of users, if at all.
</para>

</sect1>

<sect1 id="mail_example">
<title>Feedback Mail Example</title>

<para>
A typical feedback mail looks about like that:
</para>

<para>
<screen width="60">
<userinput>[kde-feedback] KDirStat-2.4.4 user feedback</userinput>

<userinput>&lt;comment&gt;</userinput>
<userinput>This is where the personal comments go.</userinput>
<userinput>You may enter virtually any number of lines.</userinput>
<userinput>&lt;/comment&gt;</userinput>

<userinput>general_opinion="5/8_nice_try"</userinput>

<userinput>features_liked="stay_on_one_filesys"</userinput>
<userinput>features_liked="feedback"</userinput>
<userinput>features_liked="pacman"</userinput>

<userinput>stability="5/5_keeps_crashing"</userinput>
<userinput>learning_curve="5/5_still_no_clue"</userinput>
<userinput>recommend="yes"</userinput>
</screen>
</para>


<para>
Notice it's all plain ASCII. There is no attachment, no hidden header fields,
no information about your machine or yourself - only what you would send to
anybody else when you send a mail.
</para>

<para>
By the way, this is also why we kept the format that simple. Many developers
today prefer XML for all kinds of data, but the end user (you) should be able
to read and understand what you send - just so you can make sure you don't send
any information you'd rather keep to yourself.
</para>

</sect1>

</chapter>


<chapter id="developers_guide">
<title>Developer's Guide to KDirStat</title>

<para>
Most of what you can see of &kdirstat; is one separate KDE widget that can be
used in other applications, too. Those parts of &kdirstat; are even licensed
under the LGPL, so you are even allowed to use it in commercial applications.
</para>

<para>
The &kdirstat; sources are extensively documented. Read the documentation in
the header files for more details or use "kdoc" to generate HTML documentation
from them.
</para>


</chapter>

<chapter id="faq">
<title>Questions and Answers</title>


&reporting.bugs;


<qandaset id="faqlist">

<qandaentry id="ftp_server">
<question>
<para>
Can I use &kdirstat; to sum up a directory on an FTP server?
</para>
</question>
<answer>
<para>
Yes. Simply specify the URL at the command line or even in &kdirstat;'s
directory selection box:
<userinput>kdirstat ftp:/ftp.myserver.org/pub</userinput> (command line) or
<userinput>ftp:/ftp.myserver.org/pub</userinput> (directory selection box).
</para>
<para>
&kdirstat; supports all protocols that KDE supports. You can even use the "tar"
protocol (does it make any sense to do that? You decide). The only restriction
is that the protocol needs to support the "list directory" service - which not
all protocols do.
</para>
<para>
If you are unsure about the syntax to use, try it in Konqueror first and look
at Konqueror's URL line. For example, to figure out how to specify a "tar" URL,
click into a "tar" archive in Konqueror and look at the resulting URL to get an
idea of what it looks like.
</para>
</answer>
</qandaentry>


<qandaentry id="exact_byte_size">
<question>
<para>
How do I get the exact byte size of an entry rather than Megabytes or
Kilobytes?
</para>
</question>
<answer>
<para>
Right-click the number in the list.
</para>
</answer>
</qandaentry>


<qandaentry id="du_reports_different_total">
<question>
<para>
Why does the "du" command sometimes report different
sizes than &kdirstat;?
</para>
</question>
<answer>
<para>
There are different kinds of sizes reported by different kinds of system calls
or KDE services: The byte size and the block size.
</para>
<para>
The byte size is the exact number of bytes of a file or directory. This is what
&kdirstat; uses.
</para>
<para>
The block size is the number of disk blocks allocated by a file or
directory. Most "du" commands use that.
Depending on the type of file system, parts of the last block of a
file or directory may be unused, yet reserved for it anyway. If such a file system
uses 1024 byte blocks, a file will at least need those 1024 bytes, no matter if
it is 1024, 200 or even just one byte large. That depends on the file system type
and sometimes even on how this is set up - i.e., this is highly system
specific.
</para>
<para>
&kdirstat; uses the byte size since this the only size that is reliably
returned by all kinds of system calls and KDE services alike. It only really
makes a difference in very pathological situations anyway, for example if you
have subdirectories with a large number of tiny files.
</para>
</answer>
</qandaentry>


<qandaentry id="sparse_files">
<question>
<para>
What does this display mean:
<userinput>
6.3 MB (allocated: 1.3 MB)
</userinput>
</para>
</question>

<answer>
<para>
This is a so-called "sparse file" (also known as "file with holes").
This means that the file really is 6.3 MB  large, but only 1.3 MB of that are
actually allocated - the rest are just zeroes.
</para>
<para>
This is typical for core dumps (memory images of crashed programs written to a
file named <userinput>core</userinput> or <userinput>core.*</userinput>)
or binary database files: The kernel writes those files in a way so only real
data content is allocated on disk and not the large amount of zeroes.
</para>
<para>
Technically, a sparse file is created with the regular open() system call to
open the file for writing, then using lseek() to extend the file size beyond
its previous size and then writing at least one byte. The area between the old
and the new file size becomes a "hole" in the file - it is not actually
allocated on the disk. Upon reading this area, a value of zero is returned for
each byte read. When bytes are written to that area, file system blocks are
actually allocated, possibly creating two smaller holes before and after the
area written to.
</para>
<para>
Please note that most file utilities do not deal graciously with sparse
files. Those that support them at all normally need special command line
arguments. Otherwise they tend to simply reading all bytes (including all the
zeroes from the holes) and writing them to a new location - which of course
means that the resulting file is no longer sparse, but really occupies all the
space its size indicates. This may mean that you can blow up the above 6.3 MB
core dump file from 1.3 MB disk usage (and 5 MB zeroes in holes) to really
6.3 MB disk usage.
</para>
<para>
GNU file system utilities like
<userinput>tar</userinput> and <userinput>rsync</userinput> at least support
command line options to prevent that.
GNU <userinput>cp</userinput> is a notable exception - it has a heuristic that
seems to work very well.
GUI driven file managers on the other hand tend to simply ignore this - even
the most modern and cool looking ones.
</para>
<para>
If in doubt, check your favourite file tools. Produce a core dump - they are
normally sparse files. The more memory a program uses, the more likely it is to
have large sections of zeroes in its memory image. Try this (in a shell):
<itemizedlist>

<listitem><para>
Enable core dumps - they are usually disabled in most Linux distributions:
</para>
<para>
<userinput>ulmit -c 128000</userinput>
</para>
<para>
This sets the limit of core dump files to 128000 blocks (512 bytes each), i.e.,
to 64 MB. This should be sufficient.
</para></listitem>

<listitem><para>
Start a program with considerable memory consumption - in the background:
</para>
<para>
<userinput>xmms &amp;</userinput>
</para></listitem>

<listitem><para>
Make the program dump core:
</para>
<para>
<userinput>kill -ABRT %xmms</userinput>
</para>
<para>
This sends the ABORT signal to this process, terminating it with a core dump.
</para></listitem>

<listitem><para>
Look at the core dump:
</para>
<para>
<userinput>kdirstat .</userinput>
</para>
<para>
or, for a neutral third-party program (from the Linux coreutils package):
</para>
<para>
<userinput>/usr/bin/stat core*</userinput>
</para>
<para>
(You need to multiply the "blocks" output with 512 to find out allocated disk space)
</para></listitem>

<listitem><para>
Copy that core dump (e.g. to another directory) and look at it again. You will
be surprised how "heavy" all those zeroes suddenly have become. Try that with
several copy utilities (<userinput>/bin/cp</userinput>, file managers of your
choice). Remember to always use the sparse original, not any blown-up copies!
</para>
<para>
Moving files should always be safe (unless a file manager is really, really
stupid), but copying can easily blow up sparse files to huge assemblies of
meaningless zeroes.
</para></listitem>

</itemizedlist>
</para>
<para>
Agreed, sparse files are rather uncommon these days, so this is usually not a
problem. Just remember &kdirstat; knows how to deal with them. ;-)
</para>
<para>
Please note that this special handling is only in effect if &kdirstat;'s
optimized read methods for local files are used (you can turn this on and off
in the <guibutton>Settings -&gt; General</guibutton> dialog) - KDE's KIO
methods do not return this kind of information.
</para>
</answer>
</qandaentry>


<qandaentry id="hard_links">
<question>
<para>
What does this display mean:
<userinput>
878.5 KB / 21 Links
</userinput>
</para>
</question>
<answer>
<para>
This means that this file has a number of hard links. &kdirstat; uses only the
respective portion of its size for its statistics - in the above case, 878.5 KB
/ 21 = 41.8 KB. When another link to this file is processed, the next 875.5/21
KB are added to the total - and so on.
</para>
<para>
The rationale is that is makes no sense to count such a file 21 times with its
full size  - this would greatly distort the statistics. For example, look at
<userinput>/usr/lib/locale</userinput> on a (SuSE) Linux system - many files
there have multiple hard links to save disk space. The total sum of that
directory on a SuSE Linux 9.2-i386 system is 40.5 MB -- as opposed to 205.6 MB
that the added-up output of <userinput>/bin/ls -lR</userinput> would suggest
(or &kdirstat; with <guibutton>use optimized local read methods</guibutton>
turned off in the <guibutton>Settings -&gt; General</guibutton> dialog)
- sometimes, as in this example, this really makes a difference!
</para>
<para>
Technical background: In Unix/Linux file systems, files primarily have a
numeric ID, their "i-number", the index of the corresponding "i-node", the file
system's administrative information. Each directory entry of a file really is
no more than a link to that i-node. You can have the very same file under
several distinct names this way - even in different directories. The only
limitation is that this is restricted to one file system (i.e. to one disk
partition) because those i-numbers are unique only per file system.
</para>
<para>
Hard links can also introduce a whole new dimenstion of problems with
applications that create backup copies of working files - they usually only
rename the original file to a backup name and write their content to a new
file. Editors usually work that way. This however means that any additional
hard links to that file now point to the outdated backup copy - which is
normally not what is desired. Only very few applications handle this
reasonably. So the bottom line is: Use hard links only if you know very well
what you are doing.
</para>
<para>
All this is probably why symbolic links have become so much more popular in recent
years: They can also point to different file systems, even (via NFS) to
different hosts in the network. On the downside, symlinks can also be stale -
pointing into nothingness. This cannot happen with hard links: A file is only
really deleted when the last of its links is deleted (this includes open
i-nodes in memory - i.e., processes still having an open file handle to that
i-node).
</para>
<para>
Directories rely completely on hard links (this is also why &kdirstat; does not
attempt to try anything smart with multiple-hard-link directories - it would
make no sense): The ".." entries in each directory pointing to its parent is
nothing else than another hard link to that parent (named ".."), and "." is
nothing else than a hard link to itself. This is also why even a completely
empty directory has a link count of 2 - one for "." in its own directory, one
for its name in its parent directory.
</para>
<para>
Like sparse files above, regular files with multiple hard links are pretty
uncommon these days - but they are still used, and sometimes they can make a
difference, and this is why &kdirstat; has special handling for them.
</para>
<para>
Please note that this special handling is only in effect if &kdirstat;'s
optimized read methods for local files are used (you can turn this on and off
in the <guibutton>Settings -&gt; General</guibutton> dialog) - KDE's KIO
methods do not return this kind of information.
</para>
</answer>
</qandaentry>


<qandaentry id="mail_client">
<question>
<para>
I don't want to use KMail every time I send a mail with &kdirstat;.
How do I tell &kdirstat; to use a different mail client?
</para>
</question>
<answer>
<para>
Start <userinput>kcontrol</userinput> or select
<guibutton>Preferences</guibutton> in the KDE menu, then select
<guibutton>Network</guibutton> -&gt; <guibutton>Email</guibutton> and enter
your favourite mail client in the <guibutton>Preferred Email client</guibutton>
field.
</para>
</answer>
</qandaentry>


<qandaentry id="tree_colors">
<question>
<para>
How do I get rid of those many percentage bar colors? I want them all displayed
in the same color.
</para>
</question>
<answer>
<para>
Select <guibutton>Configure &kdirstat;...</guibutton> from the
<guibutton>Settings</guibutton> menu, switch to the <guibutton>Tree
colors</guibutton> page and drag the slider all the way up.
</para>
</answer>
</qandaentry>


</qandaset>

</chapter>


<chapter id="credits">

<!-- Include credits for the programmers, documentation writers, and
contributors here. The license for your software should then be included below
the credits with a reference to the appropriate license file included in the KDE
distribution. -->

<title>Credits and License</title>

<para>
&kapp;
</para>
<para>
Program copyright 1999-2002 Stefan Hundhammer <email>sh@suse.de</email>
</para>

<para>
Contributors:
<itemizedlist>
<listitem>
	<para>Alexander Rawawss <email>alexannika@users.sourceforge.net</email>
	Initial treemaps (those who currently don't work any more)
	</para>
</listitem>
</itemizedlist>
</para>

<para>
Documentation copyright 2002 Stefan Hundhammer <email>sh@suse.de</email>
</para>

<!-- TRANS:CREDIT_FOR_TRANSLATORS -->

&underFDL;               <!-- FDL: do not remove. Commercial development should -->
<!-- replace this with their copyright and either remove it or re-set this.-->

&underGPL;        	 <!-- GPL License -->

</chapter>


<appendix id="installation">
<title>Installation</title>

<sect1 id="getting-kdirstat">
<title>How to obtain KDirStat</title>

<para>
&kdirstat; is part of the KDE project
<ulink url="http://www.kde.org">http://www.kde.org</ulink>.

&kdirstat; can be found on the &kdirstat; home page at
<ulink url="http://kdirstat.sourceforge.net/">http://kdirstat.sourceforge.net/</ulink>
or at the mirror site at
<ulink url="http://www.suse.de/~sh/kdirstat/">http://www.suse.de/~sh/kdirstat/</ulink>
.</para>
</sect1>

<sect1 id="requirements">
<title>Requirements</title>

<itemizedlist>
<listitem>
<para>Linux or any other Unix-type operating system.</para>
<para>As stupid as this sounds: There were quite some people complaining that
they couldn't get &kdirstat; installed on their Win9x system. Many people seem
to believe that if it has windows, it has to run on MS Windows...
</para>
</listitem>

<listitem><para>KDE 3.x</para></listitem>

</itemizedlist>

<para>
All required libraries as well as &kdirstat; itself can be found on
<ulink url="http://kdirstat.sourceforge.net/">The &kdirstat; home page</ulink>.
</para>
</sect1>


<sect1 id="compilation">
<title>Compilation and Installation</title>

<para>
See file "build-howto.html" in the distribution tarball.
</para>

</sect1>


</appendix>

&documentation.index;
</book>
<!--
Local Variables:
mode: sgml
sgml-minimize-attributes:nil
sgml-general-insert-case:lower
sgml-indent-step:0
sgml-indent-data:nil
End:
-->