Missing from manual - GETPID/GETPPID

[kenbrody]

The following was missing from the 5.6 manual, though it is in the help file.  (The manual is being updated.)

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Process information functions:
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   xx = GETPID()
   xx = GETPPID()

These return the current process ID and the parent process ID, respectively.

Note that GETPPID() returns a null value under Windows, as Windows has no concept as "parent process".