Generate random Link

Hi,

i hope one of you can help me, since im in a pretty bad situation right now.

I have a directory, that i monitor for new files. Once a new file is put in that directory, i send the link to that file - shared via apache httpd - to a given email receipient. Looks like: www.example.com/dir1/file1

My customer now wants me to implement a mechanism for a random generated link, so that no one who can guess the filename can access the file. Like a link you get, when you register somewhere with your email. If its possible, that link should only be accessable once and then be invalid.

Should look like: www.example.com/sdfogihsdfgoisd

The file must not be accessable through www.example.com/dir1/file1

i would be happy for any ideas how i can get a solution.

OS is CentOS 6.5

THX in advance.

greetings maxwell