Thank You Jan All clear!
So I need to verify my Qubide Hard Disk with Partitio.exe I don't remember with what block length I formatted that partition Andrea Il 23.07.2017 17:21 Jan Bredenbeek via Ql-Users ha scritto: > The QDOS file system stores the file position in the channel definition > block as two 16-bit words - one for the block number and one for the byte > position within one block. So, when using 512-byte blocks, the maximum file > length will be 65535*512 bytes or just under 32MB (or 16MB when using > signed arithmetic). When using 2K byte blocks, the limit will be 128 or > 64MB respectively. > > I know mdv and flp use 512-byte block size and ED flp have 2K byte sectors > but I'm not sure if the latter also uses 2K blocks. The same goes for > (virtual) win drives - sectors are usually grouped to keep the map within > limits but I don't know off-hand if that also affects the block size (it > might as well be 512 bytes, depending on the driver). > > This use of word-sized block numbers within QDOS is an unfortunate design > flaw - as is the standard FS.MDINF trap which returns word-sized sector > counts - but could TT back in 1984 foresee that within five years there > would be a storage medium for the QL that surpassed the 32MB limit? In the > PC world there are multiple examples of this - remember the 32MB partition > size limit in DOS 3.3, then the 528MB limit on CHS-addressed hard disks, > and the initial 128GB limit on LBA which was supposed to 'fix' CHS. > > Storage capacity has grown so much that any 'X MB ought to be enough for > everybody' design decision has proven wrong eventually... > > -- *Jan Bredenbeek* | Hilversum, NL | j...@bredenbeek.net [1] _______________________________________________ QL-Users Mailing List Con Mobile Open 7 GB a 9 euro/4 sett navighi veloce con 7 GB di Internet e hai 200 minuti ed SMS a 15 cent. Passa a Tiscali Mobile! http://tisca.li/Open7GB0617 _______________________________________________ QL-Users Mailing List
