Using crypt to encrypt/decrypt files

A file can be encrypted in the shell mode using crypt, or in the edit mode using the -x or X option. When you are ready to decrypt the file, you can use the crypt command in the shell mode. The following is the command format to encrypt a file:

crypt < oldfile > newfile

The system prompts you for a password.



Before removing the unencrypted oldfile, make sure the encrypted newfile can be decrypted using the appropriate password.



To decrypt a file, redirect the encrypted file to a new file you can read. The command to decrypt a file is as follows:

crypt < encrypted_file > new_filename 

Use wget to retrieve a directory of mp3s

wget -r -l1 --no-parent -A.mp3 -R.html,.gif http://www.mysite.com/mp3/

Block a particular IP address with iptables

iptables -I INPUT -s 25.25.25.25 -j DROP