#: 12286 S1/General Interest
    19-Sep-91  11:40:16
Sb: #RSDOS TO OS9
Fm: Paul Hanke 73467,403
To: anyone

  Several people have asked about transferring files from rsdos to os9 using
the utility DOSOR9.BAS,  with the main concern being the size of file
allowable.  As written, that seemed to be about 32k or 64k bytes.   I suggested
that a way to increase that to just under
100 k bytes is to add the following line:

2326 IF NN>32767 THEN NN=NN-32768:GOTO 2326  'PGH 09/09/90

  Now I'm wondering why there is still an upper limit to the transfer.  If the
size is over 100k or so, OS9 replies with a  'file too fragmented' error.  This
appears to be due to OS9's inability to keep track of where the file is if
OS9's f.a.t. needs more than 1 sector (I'm guessing mostly at this).  Since OS9
prefers to have files written to contiguous sectors, a lengthy RSDOS conversion
might appear to be fragmented even tho to RSDOS it is not, ie:
  RSDOS can use granules 32 to 68 consecutively; so far so good.  If a file
needs more room, then the order becomes 30-31, 28-29, 26-27,  etc.  instead of
0 - 31.  All this presumably because of the directory track being #17, right in
the middle of the disk.  So my reasoning is that the second half of a very long
rsdos file might appear too fragmented to OS9.  If this is the case, perhpas a
patch to rsdos to store files from granule 0 - 31 would allow DOSOR9 to
transfer a file up to 68 granules long since OS9 wouldn't have to keep track of
many non-contiguous sectors/granules.
  But I don't know that much about how OS9 keeps track of files.   
Clarification please?      -ph- 

There are 2 Replies.