read() on a deleted file

["Fasihullah Askiri" <fasihullah askiri gmail com>]

Hi all

I have a doubt regarding the behaviour of read() on an ext3
filesystem. To elucidate my doubts, I wrote a small program opens a
file and reads one byte at a time and sleeps for a while. I deleted
the file while the read was still in progress and I noticed that the
read still succeeds. How does this work? Does the kernel not free the
inode when the file is deleted but there is a pending read? To check
this, instead of deleting, I tried shred-ding the file, the read still
gets the correct data.

My questions:
- Where does the kernel get the data from?
- Is this a documented feature which I can use?
- Does shred write the file inode with junk?

Thanks for your patience
-- 
Keep Running.... And Relish the run...
+Fasih