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$ParentProcessID

FilledSmallSquare $ParentProcessID gives the ID assigned to the process which invokes the Mathematica kernel by the operating system under which it is run.

FilledSmallSquare On operating systems where no process ID is assigned, $ParentProcessID is None.

FilledSmallSquare See Section 2.14.5.

FilledSmallSquare See also: $ParentLink, $ProcessID, $CommandLine, $UserName, Environment.

FilledSmallSquare New in Version 3.