Is there disk blocks cleaning function in FreeBSD6.0?

[bwzhou]

Hello, everyone.

I used to find VOP_FREEBLK macro cleaning the content of disk blocks of a
file in 5.4, however I cannot find any kind of these operations doing the
same thing in 6.0release.

I wonder if there is any function or macro which will clean the data blocks
after the file containing these blocks is deleted in 6.0release.

Does anybody have any idea about this issue?

thanks

Zhou Bo Wen