Rotate and rename images according to their EXIF info

This is my short script to rotate and rename image files accoring to date captured based on their EXIF info.
You need jhead and exiv2 to run this. These two programs are also available in Windows and only require you to make small changes to work there as well.

#!/bin/bash -x
echo Rotating JPEG file(s)
jhead -ft -autorot D*.JPG

echo Rename(ing) file(s)
exiv2 -r '%Y%m%d-%H%M_:basename:' rename $(ls D*)

The files are then named like this (YYYYMMDD-HHDD_OriginalFileName.extension)

20120924-1320_DSC1234.JPG
20120924-1320_DSC1234.NEF
...

This script has been tested on Nikon D80 and D7000 image files.

IP address change notifier script

This is a simple bash script that is run by crontab every 5 minutes on a linux box.
It e-mails me the new address when a change of IP address is detected.

The script (ipchangemail.sh)

#!/bin/bash 

# Check if IP-address has changed. If a change has occured, mail me the new address
# Add the following line to crontab if you would like it to be run every 5 minutes:
# */5 * * * * ./ipchangemail.sh

# The network interface I want to monitor
NET_INTERFACE=eth0

# File to keep the latest IP address
IP_FILE=myip.txt

# Mail to this address when a change occur
MAILTO=mail@example.com


# Read the previous IP address from file
source $IP_FILE

CURRENT_IP=`/sbin/ifconfig $NET_INTERFACE | sed -n "/inet addr:.*255.255.25[0-5].[0-9]/{s/.*inet addr://; s/ .*//; p}"`

if [ "$CURRENT_IP" != "$OLD_IP" ]
then
        # Send email about address change
        `echo "New IP address detected: $CURRENT_IP" | mail -s "New IP address" $MAILTO`

        # Write new address to file
        `echo "OLD_IP=$CURRENT_IP" > $IP_FILE`
fi

The script can be downloaded here.

Enable query caching in mysql

Query caching is a way to increase the performance of mysql by caching database queries.
It’s quite easy to do and only requires to edit one file, in Debian it’s called /etc/mysql/my.cnf

Add the following lines in the mysqld section

[mysqld]
query-cache-type = 1
query-cache-size = 10M

restart the mysql daemon

# /etc/init.d/mysql restart

Verify that query caching is enabled

# mysql -p
Enter password:
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 33499
Server version: 5.0.32-Debian_7etch6-log Debian etch distribution

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

mysql> SHOW VARIABLES LIKE '%query_cache%';
+------------------------------+----------+
| Variable_name                | Value    |
+------------------------------+----------+
| have_query_cache             | YES      |
| query_cache_limit            | 1048576  |
| query_cache_min_res_unit     | 4096     |
| query_cache_size             | 10485760 |
| query_cache_type             | ON       |
| query_cache_wlock_invalidate | OFF      |
+------------------------------+----------+
6 rows in set (0.00 sec)

If you see something like the out above, caching is enabled.