Getting Source Code after Installing the Software

Fri Jun 16 20:27:38 UTC 2006

I installed FreeBSD on a couple of computers without installing any source code.  Now (naturally), I want to get a hold of the kernel source so I can re-compile and enable support for PIM and Multicast Routing.

However, I can't figure how to get the source off my CDs.  I downloaded the ISO's for Disk 1 and Disk 2 of FreeBSD 6.1--RELEASE.
Can anybody tell me where I can find the source code on these disks so I don't have to run a re-installation just to get it??

Thanks,

Rich Mayo