how to restore /usr/src

[Nerius Landys]

>how can i reinstall the original /usr/src

 Oh that's really easy.  Don't fret.  I delete it all the time and get it
back in the following way.

In the handbook, there's a section about synchronizing your source:
http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/synching.html

Use 'cvsup' or 'csup'; if your system is newer 'csup' will be part of the
system.  Find your 'standard-supfile' file (probably in
/usr/share/examples/cvsup/standard-supfile), copy it to your home directory
and modify it by changing the lines

*default host=CHANGE_THIS.FreeBSD.org (change 'CHANGE_THIS' to 'cvsup11.us'
for example)
*default release=cvs tag=<CVS TAG> (see below)

and then run 'csup standard-supfile' or 'cvsup standard-supfile'.

'cvsup' is in /usr/ports/net/cvsup-without-gui if you need to install it.
CVS TAGs are explained in
http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/cvs-tags.html