Rename files in a directory randomly

Using Terminal – 

Go to that folder and run the following : 


for file in *.txt ; do
   name=$(tr -dc "[:alnum:]" < /dev/urandom | head -c 10)
   mv "$file" ${name}.txt

instead of “.txt” any other extension may be used.
We can change :alnum: to :digit: or :alpha: depending on what we want.


How can I change permissions of a folder, including its enclosed files and subdirectories?

If you want to give everybody a read/write permission you should add ‘a’ to your command so that it will be chmod -R uga+rw.

Using terminal command
 chmod -R uga+rw /opt/lampp/*