OK... I have a major problem if someone could be kind enough and had the time to email me a program C for ubuntu that does the following i would be mostly obliged :)) :
A process of father create (fork) a son and will sleep 90 minutes..After this, son process create a grandchild and will sleep 60 minutes..Grandchild process will sleep for 30 minutes..After sleep,each process must write a message about which process is itself and what its PID is.