Orphan Processes
Orphan processes is kind of the opposite situation of zombie processes, since it refers to the case where a parent process terminates before its child processes, in which case these children are said to become "orphaned".
Unlike the assynchronous child-to-parent notification that happens when a child process terminates (via the SIGCHLD signal), child processes are not notified immediately when their parent finishes. Instead, the system simply redefines the "parent-pid" field in the child process's data to be the process that is the "ancestor" of every other process in the system, whose pid generally has the value 1 (one), and whose name is traditionally "init". It is thus said that "init 'adopts' every orphan process on the system".
A somewhat common assumption by programmers new to UNIX is that the child processes of a terminating process will be adopted this process's immediate parent process (hence those child processes' "grandparent"). Such assumption is incorrect—unless, of course, that "grandparent" is init itself.
Read more about this topic: Parent Process
Famous quotes containing the words orphan and/or processes:
“A man should not go where he cannot carry his whole sphere or society with him,Mnot bodily, the whole circle of his friends, but atmospherically. He should preserve in a new company the same attitude of mind and reality of relation, which his daily associates draw him to, else he is shorn of his best beams, and will be an orphan in the merriest club.”
—Ralph Waldo Emerson (1803–1882)
“It has become a people’s war, and peoples of all sorts and races, of every degree of power and variety of fortune, are involved in its sweeping processes of change and settlement.”
—Woodrow Wilson (1856–1924)