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how to replace line on particular line in file[no need to write it back whole file again]

On 2018-10-12 22:28:44 -0400, Dennis Lee Bieber wrote:
> On Fri, 12 Oct 2018 21:00:45 +0200, "Peter J. Holzer" <hjp-python at hjp.at>
> declaimed the following:
> >I don't know if there was a C implementation for CP-V, but there is
> >certainly nothing in the C standard which would prevent a standard
> >conforming implementation of those file organizations.
> 	However -- my point was that those formats were supported natively at
> the OS level, not some language utility library working on top of the basic
> streams.

Right. And since this is an OS capability (which Unix lacks), not a
language capability, I think it is better to talk about Unix-style
streams, not C-style streams.

> 	A more recent (my age shows) example would be the features in DEC VMS
> Record Management Services. Again the format was handled at the system
> service level by any language -- stream, fixed length with counts, ISAM...

Any language includes C. I haven't programmed in C on VMS, but my
understanding is that the C library works works fine with fixed length
records on VMS. Indeed I think that VMS was a major reason for some
restrictions in the C standard.


   _  | Peter J. Holzer    | we build much bigger, better disasters now
|_|_) |                    | because we have much more sophisticated
| |   | hjp at hjp.at         | management tools.
__/   | http://www.hjp.at/ | -- Ross Anderson <https://www.edge.org/>
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