Vorige                       Titel                            Volgende
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The contents of a directoryentry is as follows:

- A link to the next directoryentry in this directory
- A name
- A link to the 'contents' of this directoryentry
   (An UFI, program or directory)
- status containing among others:
    - The type of the contents of this directory.
- The number of pointers to this directoryentry. This number is
  kept updated and if it decrements to zero the directoryentry is killed.

If the Directoryentry contains a directory the link points to the
forst directoryentry of that directory.


A program is stored in the following way:

- Status   (Is this programcode approved or not)
- number of links to this block. (One program may re represented
  by more than one directoryentry. If this number is decremented
  to zero the program is thrown away.
- The amount of initial RAM the task needs
- The length of the program
- The programcode itself.




All the free RAM is linked in a list. The smallest pieces are at the
beginning of the list and the larger ones at the end. As these links
are stored in free memory they do not occupy any memory wich the
system might want  to use. If a piece of memory comes free it is put
in the list at it's proper place after it has been checked that it
doesn't form a larger piece of free memory together with another
piece already in the list. When a piece of memory is needed the
first piece in the list is used wich is large enough. This ensures
the optimum use of the memory.

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Vorige                       Titel                            Volgende