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Delete Files Older Than x Days on Linux

The find utility on linux allows you to pass in a bunch of interesting arguments, including one to execute another command on each file. We'll use this in order to figure out what files are older than a certain number of days, and then use the rm command to delete them.

Command Syntax

find /path/to/files* -mtime +5 -exec rm {} \;

Note that there are spaces between rm, {}, and \;

Explanation

• The first argument is the path to the files. This can be a path, a directory, or a wildcard as in the example above. I would recommend using the full path, and make sure that you run the command without the exec rm to make sure you are getting the right results.
• The second argument, -mtime, is used to specify the number of days old that the file is. If you enter +5, it will find files older than 5 days.
• The third argument, -exec, allows you to pass in a command such as rm. The {} \; at the end is required to end the command.

This should work on Ubuntu, Suse, Redhat, or pretty much any version of linux.

GNU’s wget command line program for downloading is very popular, and not without reason. While you can use it simply to retrieve a single file from a server, it is much more powerful than that and offers many more features.

One of the more advanced features in wget is the mirror feature. This allows you to create a complete local copy of a website, including any stylesheets, supporting images and other support files. All the (internal) links will be followed and downloaded as well (and their resources), until you have a complete copy of the site on your local machine.

In its most basic form, you use the mirror functionality like so:

$ wget -m http://www.example.com/

There are several issues you might have with this approach, however.

First of all, it’s not very useful for local browsing, as the links in the pages themselves still point to the real URLs and not your local downloads. What that means is that, if, say, you downloaded http://www.example.com/, the link on that page to http://www.example.com/page2.html would still point to example.com’s server and so would be a right pain if you’re trying to browse your local copy of the site while being offline for some reason.

To fix this, you can use the -k option in conjunction with the mirror option:

$ wget -mk http://www.example.com/

Now, that link I talked about earlier will point to the relative page2.html. The same happens with all images, stylesheets and resources, so you should be able to now get an authentic offline browsing experience.

There’s one other major issue I haven’t covered here yet - bandwidth. Disregarding the bandwidth you’ll be using on your connection to pull down a whole site, you’re going to be putting some strain on the remote server. You should think about being kind and reduce the load on them (and you) especially if the site is small and bandwidth comes at a premium. Play nice.

One of the ways in which you can do this is to deliberately slow down the download by placing a delay between requests to the server.

$ wget -mk -w 20 http://www.example.com/

This places a delay of 20 seconds between requests. Replace that number, and optionally you can add a suffix of m for minutes, h for hours, and d for … yes, days, if you want to slow down the mirror even further.

Now if you want to make a backup of something, or download your favourite website for viewing when you’re offline, you can do so with wget’s mirror feature. To delve even further into this, check out wget’s man page (man wget) where there are further options, such as random delays, setting a custom user agent, sending cookies to the site and lots more.

RarCrack Opens Protected Archives Without Passwords

Adjust Volume of Individual Applications with PulseAudio

Index of /Tests/Tutorial

File	Rev.	Age	Author	Last log entry
Parent Directory
Step1/
Step2/
Step3/
Step4/
Step5/
Step6/
Step7/

POTATOES

An old man lived alone in the country. He wanted to dig his potato garden but it was very hard work as the ground was hard. His only son Fred, who used to help him, was in prison. The old man wrote a letter to his son and described his predicament.

Dear Fred,
I am feeling pretty bad because it looks like I won't be able to plant my potato garden this year. I'm just getting too old to be digging up a garden plot. If you were here, all my troubles would be over I know you would dig the plot for me.
Love,
Dad

A few days later he received a letter from his son.

Dear Dad,
For heaven's sake, don't dig up that garden! That's where I buried the BODIES!
Love,
Fred

At 4am the next morning, FBI agents and local police arrived and dug up the entire area without finding any bodies. They apologized to the old man and left. That same day the old man received another letter from his son.

Dear Dad,
Go ahead and plant the potatoes now. That's the best I could do under the circumstances.
Love,
Fred

Karen Reid

Lecturer in Department of Computer Science at the University of Toronto.

TA Training

Courses Taught

Fall 2002

• csc150 Accelerated Introduction to Computer Science
• csc209 Software Tools and Systems Programming

Research

The general area of my research is in resource management for clusters of computers. I have been looking at how to more efficiently transfer large data sets from external storage servers onto the local disks of the cluster for use during computation.

"Overlapping Data Transfer With Application Execution on Clusters", Karen Reid and Michael Stumm appeared in the Workshop on Cluster Based Computing at ICS 2000. (postscript, pdf )

Address

E-Mail: reid@cs.utoronto.ca (Current students should use the course specific email address.)

Office: BA 4240
Dept Phone: (416) 978-6025
Fax: (416) 978-1931
Office Phone: (416) 978-7797

Jonathon Edington

Walmart Growth Video

March 20th, 2008 toby |

Trac on Ubuntu ¶

These instructions were written for a fresh install of Ubuntu. This documentation suggests performing custom install when installing Ubuntu to create a base system without an X server or other graphical niceties. These instructions, however, should work reasonably well if you already have Ubuntu installed or you have performed a full install.

Breezy users: See comments below for some of the problems encountered.

Dapper users: should work fine with the following instructions.

Note: For an alternative Ubuntu experience, using apache and configuring for multiple projects, see TracUbuntuMultipleProjects

Also see: https://help.ubuntu.com/community/UbuntuTracHowto

Installation ¶

1. Install Software Packages ¶

To install Trac on your system, install the trac and libapache2-svn packages:

sudo apt-get install trac apache2 libapache2-svn

2. Create the Trac Environments Directory ¶

You'll need a directory for Trac's environments to live that should be writable by the default Apache user:

sudo mkdir /var/lib/trac
sudo chown www-data:www-data /var/lib/trac

If you put your environment somewhere else, make sure to note that and use that location in the appropriate places in the next step.

3. Setup Apache2 ¶

Next, create a new Apache-2 virtualhost by saving the following as /etc/apache2/sites-available/trac :

<VirtualHost *>
        ServerAdmin webmaster@localhost
        ServerName trac.example.com
        DocumentRoot /usr/share/trac/cgi-bin/
        <Directory /usr/share/trac/cgi-bin/>
                Options Indexes FollowSymLinks MultiViews ExecCGI
                AllowOverride All
                Order allow,deny
                allow from all
        </Directory>
        Alias /trac "/usr/share/trac/htdocs"

        <Location /trac.cgi>
            SetEnv TRAC_ENV "/var/lib/trac/YourProjectNameHere"
        </Location>

        DirectoryIndex trac.cgi
        ErrorLog /var/log/apache2/error.trac.log
        CustomLog /var/log/apache2/access.trac.log combined
</VirtualHost>

Note: If you get errors later that pertain to environment look at SetEnv TRAC_ENV. You can also use SetEnv TRAC_ENV_PARENT_DIR "/var/lib/trac" to host multiple projects.

You also need to uncomment the AddHandler line in /etc/apache2/apache2.conf so that the Trac CGI program will be executed:

# To use CGI scripts outside /cgi-bin/:
#
AddHandler cgi-script .cgi

Now, disable the default virtualhost, enable the Trac virtualhost, and restart Apache2:

sudo a2dissite default
sudo a2ensite trac
sudo  /etc/init.d/apache2 reload 

If you are going to want to login, you're going to need authentication. I added the following to my virtual host file to get this to work:

        <Location "/trac.cgi/login">
            AuthType Basic
            AuthName "Trac"
            AuthUserFile /etc/apache2/dav_svn.passwd
            Require valid-user
        </Location>

This will share the password with your subversion install. You'll also need to grant each user rights using trac-admin.

Alternately, you can use htpasswd to create an htpasswd file, and point AuthUserFile? at that location.

4. Creating Environments ¶

I installed my Subversion repository at /var/lib/svn/YourProjectNameHere. So I did a quick starting config of subversion with the following commands:

sudo mkdir /var/lib/svn
sudo mkdir /var/lib/svn/YourProjectNameHere
sudo mkdir /tmp/YourProjectNameHere
sudo mkdir /tmp/YourProjectNameHere/branches
sudo mkdir /tmp/YourProjectNameHere/tags
sudo mkdir /tmp/YourProjectNameHere/trunk
sudo svnadmin create /var/lib/svn/YourProjectNameHere
sudo svn import /tmp/YourProjectNameHere file:///var/lib/svn/YourProjectNameHere -m "initial import"
sudo rm -rf /tmp/YourProjectNameHere

Some permissions changes and an apache restart are now needed:

sudo chown -R www-data /var/lib/svn/YourProjectNameHere
sudo chown -R www-data /usr/share/trac
sudo apache2 -k restart

Test by web-browsing to http://servername/svn/YourProjectNameHere

If you see a simple web page which says Revision 1: / and lists branches, tags, and trunk, your Subversion install is up and running!

Here's what to do if you see 404 Not Found

Check you Subversion installation, specifically /etc/apache2/mods-available/dav_svn.conf and make sure you really have a valid configuration. Still having problems see Ubuntu SVN documentation

Now let's finish the Trac install (but don't go on to Trac install until you have the above working properly).

I put my trac environment at /var/lib/trac/YourProjectNameHere. Of course you could use any other path or name - something a little more descriptive of your project would probably be a good idea. First I ran these commands:

sudo mkdir /var/lib/trac
sudo trac-admin /var/lib/trac/YourProjectNameHere initenv
sudo chown -R www-data /var/lib/trac/YourProjectNameHere

The "trac-admin" command shown above prompted me to enter:

• the project name (YourProjectNameHere)
• the path to svn repository (/var/lib/svn/YourProjectNameHere)
• the path to the Trac templates directory (/usr/share/trac/templates)

... then it prints out a bunch of stuff. If there are no errors you should now be able to surf to your Trac site at http://servername/trac.cgi

At the time I did my install, there was one glitch in the Ubuntu Universe Trac installer. It doesn't install the neo_cgi.so file needed in the python2.4 directory space. So when I surfed to my Trac site, I got the error ImportError: No module named neo_cgi. I was able to fix this by symlinking the python2.3 version like so:

sudo ln -s /usr/lib/python2.3/site-packages/neo_cgi.so /usr/lib/python2.4/site-packages/neo_cgi.so

Voila! Your Trac system & website should be up and running.

 http://reddit.com/user/earobinson/liked.rss

ac S -style ock n avaScript

Apple’s Mac OS X operating system is renowned for its fluid graphical effects. One impressive feature is the dock’s ‘fish-eye’ effect, whereby icons expand and contract as the mouse moves over them. Achieving this effect in JavaScript is difficult, but the MacStyleDock function allows this feature to be implemented easily. An example is shown below (a larger demonstration is available on a separate page).

Compatible browsers

The code has been tested and works in the following browsers:

• Firefox 1.5 on Mac OS X
• Firefox 2 on Ubuntu Linux
• Firefox 2 on Windows (slightly jerky due to event handlers being given a higher priority than intervals)
• Internet Explorer 6
• Internet Explorer 7
• Konqueror 3.5 on Ubuntu Linux
• Opera 9 on Windows
• Safari 2 on Mac OS X

Implementing the Mac-style Dock

File	Size	Description
MacStyleDock.js	6285 bytes	Full version with comments
MacStyleDock.compressed.js	2632 bytes	Compressed version

Download one of the files listed above and upload it to your website. Link to it from your page with code such as:

<script type="text/javascript" src="MacStyleDock.js"></script>

The code for the dock is added to the document tree under an existing node, so create an element to contain with code such as:

<div id="dock"></div>

The dock can then be created as a new JavaScript object. Note that the dock’s document tree node must already exist when the constructor is called. This can be done either by including the JavaScript code below the node in the document source, or by calling the constructor when the document has loaded — one way to do this is by using the OnloadScheduler.

The constructor takes five paramaters:

node

The node at which to create the Mac-style dock.

imageDetails

An array each of whose elements are object with three properties:

name

the basename of the image

sizes

an array of pizel sizes available

extension

the image extension

onclick

the function to call when the image is clicked

Requested file names consist of the concatenation of the name property, one of the values of the size property, and the extension property.

minimumSize

The minimum size of icons in the dock.

maximumSize

The maximum size of icons in the dock.

range

The range of expansion, measured in icons. This need not be an integer.

For example:

<script type="text/javascript" >
  var dock = new MacStyleDock(
      document.getElementById('dock'),
      [
        {
          name:      'mac-icon-0-',
          extension: '.jpg',
          sizes:     [32,64],
          onclick:   function(){
                       alert('You clicked on the first icon');
                     }
        },
        {
          name:      'mac-icon-1-',
          extension: '.jpg',
          sizes:     [32,64],
          onclick:   function(){
                       alert('You clicked on the second icon');
                     }
        }
      ],
      32,
      64,
      2.5);
</script>

Multiple icon sizes should be supplied for operating systems such as Windows that scale images poorly. The function will scale down the next larger image from the size it requires.

Further reading

If you’re looking for a JavaScript book, one of the best is the 1000-page JavaScript: The Definitive Guide by David Flanagan, published by O’Reilly and now in its fifth edition. It covers all aspects of JavaScript and details the most common browser compatibility issues that you may encounter:

• JavaScript: The Definitive Guide at Amazon.com
• JavaScript: The Definitive Guide at Amazon.co.uk (for British readers)

• Safalra’s Website
• Web Design
• JavaScript
• A Mac OS X-style Dock In JavaScript