Any doc reference on /entropy file ?

[Bernard Dugas]

Hi,

When i look at / in a standard installation like :
FreeBSD XXX 7.0-RELEASE FreeBSD 7.0-RELEASE #0: Sun Feb 24 19:59:52 UTC 
2008     root at logan.cse.buffalo.edu:/usr/obj/usr/src/sys/GENERIC  i386

There is only 1 file, named entropy :

-rw-------   1 root  wheel  4096 Dec 11 17:36 entropy

I can't find any reference to that file in FreeBSD doc.

Any reference to it ? What is it used for ? I have look in RANDOM area, 
but no reference...

Do i have to keep it read/write ? Can i put it in /var instead of / to 
be able to keep / read-only ?

Thanks a lot,
Best regards,