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This information can be accessed by applications by using the OS_Frm system call, to read file attributes, and specifying a handle of $FFFF in the IX register pair. Note that although the sequential pointer (PTR) and extent (EXT) are returned as 4 byte values in DE and BC registers, the end of file (EOF) result is returned in Fz, with Fz = 1 indicating the end of file (ie. TRUE or 1) and Fz = 0 otherwise (ie. FALSE or 0).
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