You are absolutely right!. The strange behavior is occuring because when I add a line "a b c" i don't press enter after it.

If I do, then the utiltity works the way I want to (except that I have to wait for 10 seconds to see the changes... I would like to reduce this to one second).

Also, Does the unix tail -f utiltity also depend on the carriage return at the end of the line?

regards,
Abhishek.