[Info-vax] Anyone interested in another public access system

[Bob Eager]

On Wed, 15 Apr 2009 20:31:07 UTC, "P. Sture" 
<paul.sture.nospam at hispeed.ch> wrote:

> In article <gs2jq1$c44$3 at naig.caltech.edu>,
>  glen herrmannsfeldt <gah at ugcs.caltech.edu> wrote:
> 
> > In the days of small memory, caching files in memory was
> > not possible.  The RT-11 file system allocates contiguously.
> > As I remember, the first file open is at the beginning of the largest
> > free area.  When another file is open, it is either at the
> > beginning of another large free area, or at the middle of the
> > free area being used by the previously opened file.  
> 
> I can't remember whether it was a DIBOL specific thing, but on the RT-11 
> systems I worked with when opening a sequential file for output, the 
> allocation made was half of that free space, truncating at file close. 
> Therefore if more than one sequential output file was opened at the same 
> time, you _would_ get fragmentation. When an output file became full, 
> the system would ask you for a continuation file specification, then 
> continue.

ISTR that on RT-11 (when I used it) part of the output filespec could 
include a value for the file size (possibly in square brackets). This 
was probably a function of the command interpreter but presumably it had
a programmatic analogue.

-- 
Bob Eager