...
If IX(in) = $FFFF then the following information is obtained:
FA_PTR:
DE = number of free handles
BC = OZ version number (OZ version is embedded in C register as two hex nibbles, ie. 44H for OZ V4.4)
FA_EXT:
DEBC = estimate of free memory
FA_EOF:
Fz = 1, if Z88 is expanded, else Fz = 0
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