reference counting

programming A garbage collection technique where each

memory cell contains a count of the number of other cells

which point to it. If this count reaches zero the cell is

freed and its pointers to other cells are followed to

decrement their counts, and so on recursively.

This technique cannot cope with circular data structures.

Cells in such structures refer (indirectly) to themselves and

so will never have a zero reference count. This means they

would never be reclaimed, even when there are no references

from outside the structure.

(1995-02-22)