IN: IX = filter handle OUT, if call successful: Fc = 0 OUT, if call failed: Fc = 1 A = error code: RC_HAND ($08), bad filter handle RC_PUSH ($0E), push back error 1. never read from filter 2. Already pushed back one character RC_EOF ($09), filter is empty Registers changed after return: ..BCDEHL/IXIY same AF....../.... different |
At most one character can be pushed back without an intervening read, otherwise a push back error is given.
GN_Flc, close filter
GN_Flf, flush filter
GN_Flo, open filter
GN_Flr, read from filter
GN_Flw, write character to filter