urldecode - decodes strings according to RFC 1738
urlencode [-m|-d] string [string ...]
The urlencode command line tool is not installed by default in linux.
$ sudo apt-get install gridsite-clients
d - decode
string - The url string to be decoded.
The decoded url
$ urlencode -d "http%3A%2F%2Fexample.com%2F%3Fq%3Dlinux%2Burl%2Bdecode"
http://example.com/?q=linux+url+decode