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**Rog131** · Dec 25, 2007, 02:32 AM

Re: HOWTO : Cleaning old KDE thumbnails

Using ImageMagick's identify command to screen obsolete thumbnails.

man identify:

identify(1) identify(1)

NAME
identify - describes the format and characteristics of one or more
image files.

SYNOPSIS
identify [options] input-file

OVERVIEW
The identify program is a member of the ImageMagick(1) suite of tools.
It describes the format and characteristics of one or more image files.
It also reports if an image is incomplete or corrupt. The information
returned includes the image number, the file name, the width and height
of the image, whether the image is colormapped or not, the number of
colors in the image, the number of bytes in the image, the format of
the image (JPEG, PNM, etc.), and finally the number of seconds it took
to read and process the image. Many more attributes are available with
the verbose option.

For more information about the identify command, point your browser to
file:///usr/share/doc/imagemagick/www/identify.html or
http://www.imagemagick.org/script/identify.php.

This script simply checks is there original file. If not, it removes thumbnail picture. There is also expiration check for the thumbnails.

Code:

#!/bin/sh

# Expiration age of thumbnails (days).
EXPIRE=30
# Path to thumbnails
THUMB=/home/<user>/.thumbnails

DLIST=`ls -1 $THUMB`

for D in $DLIST
do
 FLIST=`find $THUMB/$D/ -name "*.png" -exec ls {} \;`
 for F in $FLIST
 do
#  Parsing ImageMagick's output.
   O=`identify -verbose $F | grep -v "Thumbnail of file:" | grep "file:"| sed s/"Thumb::URI:"//g | sed s/"file:\/\/"//g`
   if [ -f $O ];
#    Original file exist.
    then
#     Removing expired thumbnail.
      find $F -mtime +$EXPIRE -exec rm -f {} \;
#    Original file does not exist.
    else
#     Removing obsolete thumbnail.
      rm -f $F
   fi
 done
done

Note
<user> is your username.

Update. A bit better (?) version:

Using extract command to screen obsolete thumbnails.

Code:

#!/bin/sh

# Expiration age of thumbnails (days).
EXPIRE=30
# Path to thumbnails
THUMB=/home/<user>/.thumbnails

DLIST=`ls -1 $THUMB`

for D in $DLIST
do
 FLIST=`find $THUMB/$D/ -name "*.png" -exec ls {} \;`
 for F in $FLIST
 do
#  parsing extracts's output.
   O=`extract $F | grep "file:"| sed s/"unknown - file:\/\/"//g | sed s/"%20"/" "/g`
   if [ -f "$O" ];
#    Original file exist.
    then
#     Removing expired thumbnail.
      find $F -mtime +$EXPIRE -exec rm -f {} \;
#    Original file does not exist.
    else
#     Removing obsolete thumbnail.
      rm -f $F
   fi
 done
done

man extract

NAME
extract - determine meta-information about a file

SYNOPSIS
extract [ -abdfghLnrsvV ] [ -B language ] [ -H hash-algorithm ] [ -l library ] [ -p type ] [ -x type ] file ...

Package: extract

displays meta-data from files of arbitrary type

Similar to the well-known "file" command, extract can display meta-data from a
file and print the results to stdout...

Anacron will do the check if you drop the script in the /etc/cron.daily. Other places: FAQ: How to start programs when KDE starts or stops

Tools for cleaning:

kleansweep - File cleaner for KDE

File cleaner for KDE
KleanSweep allows you to reclaim disk space by finding unneeded files.
It can search for files basing on several criterias; you can seek for:
- empty files
- empty directories
- backup files
- broken symbolic links
- broken executables (executables with missing libraries)
- dead menu entries (.desktop files pointing to non-existing executables)
- duplicated files
- orphaned files -- files not found in RPM (for rpm-based distros, e.g.
Fedora Core, Suse) or DPKG (for dpkg based distros, e.g. Debian and Ubuntu)
database
- obsolete thumbnails (thumbnails conforming to freedesktop.org standard,
pointing to non-existing images)

Homepage: http://linux.bydg.org/~yogin/

Cleaning up a Ubuntu GNU/Linux system
http://www.ubuntugeek.com/cleaning-u...in-ubuntu.html

Links

Introduction to ImageMagick
http://www.imagemagick.org/script/index.php

ImageMagic:Command-line Tools:Identify
http://www.imagemagick.org/script/identify.php

"Argument list too long": Beyond Arguments and Limitations
http://www.linuxjournal.com/article/6060

/bin/rm annoying limitation: Argument list too long
http://www.ducea.com/2006/05/24/binr...list-too-long/

**Rog131** · Dec 25, 2007, 02:38 AM

Re: HOWTO : Cleaning old KDE thumbnails

Using Anacron

About anacron
http://en.wikipedia.org/wiki/Anacron

1) Simply put executable /1/ script file in the /etc/cron.daily, /etc/cron.weekly or /etc/cron.monthly.
2) Touch the script file:

Code:

sudo touch /etc/cron.daily/scriptfile

man touch:

TOUCH(1) User Commands TOUCH(1)

NAME
touch - change file timestamps

SYNOPSIS
touch [OPTION]... FILE...

DESCRIPTION
Update the access and modification times of each FILE to the current
time.

Mandatory arguments to long options are mandatory for short options
too.

-a change only the access time

-c, --no-create
do not create any files

-d, --date=STRING
parse STRING and use it instead of current time

Testing scripts with anacron

man anacron:

ANACRON(8) Anacron Users’ Manual ANACRON(8)

NAME
anacron - runs commands periodically

SYNOPSIS
anacron [-s] [-f] [-n] [-d] [-q] [-t anacrontab] [-S spooldir] [job]
...
anacron [-S spooldir] -u [-t anacrontab] [job] ...
anacron [-V|-h]
anacron -T [-t anacrontab]

DESCRIPTION
Anacron can be used to execute commands periodically, with a frequency
specified in days. Unlike cron(8), it does not assume that the machine
is running continuously. Hence, it can be used on machines that aren’t
running 24 hours a day, to control daily, weekly, and monthly jobs that
are usually controlled by cron.

When executed, Anacron reads a list of jobs from a configuration file,
normally /etc/anacrontab (see anacrontab(5)). This file contains the
list of jobs that Anacron controls.

Test run:

Code:

sudo anacron -f -d

-f Force execution of the jobs, ignoring the timestamps.
-d Don’t fork to the background. In this mode, Anacron will output
informational messages to standard error, as well as to syslog.
The output of jobs is mailed as usual.

Anacron messages in the log:

Code:

grep anacron /var/log/syslog

Anacron keeps timestamps in the /var/spool/anacron/. If you remove cron.daily, cron.weekly or cron.monthly files from there, anacron will execute daily, weekly or monthly scripts at the next startup.

/1/ To make script executable:
Dolphin/Konqueror, right click script > Properties > Permissions > is executable.
or

Code:

chmod +x /path/to/script.sh

man chmod

CHMOD(1) User Commands CHMOD(1)

NAME
chmod - change file access permissions

SYNOPSIS
chmod [OPTION]... MODE[,MODE]... FILE...
chmod [OPTION]... OCTAL-MODE FILE...
chmod [OPTION]... --reference=RFILE FILE...

DESCRIPTION
This manual page documents the GNU version of chmod. chmod changes the
permissions of each given file according to mode, which can be either a
symbolic representation of changes to make, or an octal number repre‐
senting the bit pattern for the new permissions.

Links:

chmod Tutorial
http://catcode.com/teachmod/

18.4. Configure the /etc/cron.daily/tripwire.verify script
http://www.faqs.org/docs/securing/chap18sec147.html

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HOWTO : Cleaning old KDE thumbnails

HOWTO : Cleaning old KDE thumbnails

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