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Groups > comp.sys.acorn.programmer > #1502
| Date | 2012-03-13 07:44 +0000 |
|---|---|
| From | Matthew Phillips <spam2011m@yahoo.co.uk> |
| Newsgroups | comp.sys.acorn.programmer |
| Subject | Re: OS_GBPB 12 in a Wimp task |
| Message-ID | <bd6eb36f52.Matthew@sinenomine.freeserve.co.uk> (permalink) |
| References | (1 earlier) <9fa95124-990a-43e2-a561-b4c03bff439c@p7g2000yqk.googlegroups.com> <cf9d716d52.Matthew@sinenomine.freeserve.co.uk> <dea93483-8f06-4b66-8cd0-91b1968f3694@em9g2000vbb.googlegroups.com> <526e81074bchrisjohnson+news@spamcop.net> <ba7532b4-82ff-418c-9f3e-96e7083ccbba@w5g2000vbv.googlegroups.com> |
In message <ba7532b4-82ff-418c-9f3e-96e7083ccbba@w5g2000vbv.googlegroups.com> on 12 Mar 2012 jeff wrote: > When the Filer scans through the directory deleting files it decrements R4 > by one for each file deleted. However on FAT media the file is only marked > as deleted and the entry is not removed from the directory, hence R4 needs > to remain the same. > > So the fiddle that I have used here is to return in R4 the number shifted > left 8 places and 0x80 added. This means that if the Filer alters R4 by a > small amount it will not change the upper 24 bits. That's a nice solution, and I clearly ought to adopt something similar if I ever release a new version of CPMFS. I wonder whether DOSFS employs a similar trick. You're relying here on FilerAction never operating on more than 256 objects at once, but Chris Bazley's reading of the source code suggests 20 at most is the maximum. If FilerAction is not going to be fixed, then it is essential that filing system authors are made aware of these constraints and (mis-)uses of R4. PRM 2 says nothing to make you suppose you'd have to deal with situations like this. How did you work out what to do, by the way? Did you get strange things happening and have to come up with the fix? -- Matthew Phillips Durham
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OS_GBPB 12 in a Wimp task Christopher Bazley <cs99cjb@gmail.com> - 2012-03-06 14:33 -0800
Re: OS_GBPB 12 in a Wimp task jeff <jeffrey.a.doggett@gmail.com> - 2012-03-07 00:02 -0800
Re: OS_GBPB 12 in a Wimp task Matthew Phillips <spam2011m@yahoo.co.uk> - 2012-03-08 22:33 +0000
Re: OS_GBPB 12 in a Wimp task Christopher Bazley <cs99cjb@gmail.com> - 2012-03-10 10:22 -0800
Re: OS_GBPB 12 in a Wimp task Matthew Phillips <spam2011m@yahoo.co.uk> - 2012-03-10 21:04 +0000
Re: OS_GBPB 12 in a Wimp task Rick Murray <heyrickmail-usenet@yahoo.co.uk> - 2012-03-10 23:11 +0100
Re: OS_GBPB 12 in a Wimp task Matthew Phillips <spam2011m@yahoo.co.uk> - 2012-03-11 09:10 +0000
Re: OS_GBPB 12 in a Wimp task Chris Johnson <chrisjohnson+news@spamcop.net> - 2012-03-11 10:41 +0000
Re: OS_GBPB 12 in a Wimp task Steve Fryatt <news@stevefryatt.org.uk> - 2012-03-11 11:06 +0000
Re: OS_GBPB 12 in a Wimp task Rick Murray <heyrickmail-usenet@yahoo.co.uk> - 2012-03-11 17:56 +0100
Re: OS_GBPB 12 in a Wimp task Gavin Wraith <gavin@wra1th.plus.com> - 2012-03-11 18:25 +0000
Re: OS_GBPB 12 in a Wimp task Rick Murray <heyrickmail-usenet@yahoo.co.uk> - 2012-03-12 00:33 +0100
Re: OS_GBPB 12 in a Wimp task Gavin Wraith <gavin@wra1th.plus.com> - 2012-03-12 11:56 +0000
Re: OS_GBPB 12 in a Wimp task Martin Wuerthner <spamtrap@mw-software.com> - 2012-03-12 16:44 +0100
Re: OS_GBPB 12 in a Wimp task druck <news@druck.org.uk> - 2012-03-12 20:57 +0000
Re: OS_GBPB 12 in a Wimp task Martin Wuerthner <spamtrap@mw-software.com> - 2012-03-12 22:26 +0100
Re: OS_GBPB 12 in a Wimp task Rick Murray <heyrickmail-usenet@yahoo.co.uk> - 2012-03-13 17:50 +0100
Re: OS_GBPB 12 in a Wimp task jgharston <jgh@arcade.demon.co.uk> - 2012-03-13 10:15 -0700
Re: OS_GBPB 12 in a Wimp task Matthew Phillips <spam2011m@yahoo.co.uk> - 2012-03-13 07:34 +0000
Re: OS_GBPB 12 in a Wimp task Rick Murray <heyrickmail-usenet@yahoo.co.uk> - 2012-03-14 06:00 +0100
Re: OS_GBPB 12 in a Wimp task Christopher Bazley <cs99cjb@gmail.com> - 2012-03-15 02:40 -0700
Re: OS_GBPB 12 in a Wimp task Rick Murray <heyrickmail-usenet@yahoo.co.uk> - 2012-03-15 14:55 +0100
Re: OS_GBPB 12 in a Wimp task "Ste (news)" <steve@revi11.plus.com> - 2012-03-15 14:46 +0000
Re: OS_GBPB 12 in a Wimp task Rick Murray <heyrickmail-usenet@yahoo.co.uk> - 2012-03-15 18:44 +0100
Re: OS_GBPB 12 in a Wimp task Jeremy Nicoll - news posts <jn.nntp.scrap007@wingsandbeaks.org.uk> - 2012-03-15 19:44 +0000
Re: OS_GBPB 12 in a Wimp task Alan Adams <alan@adamshome.org.uk> - 2012-03-15 20:36 +0000
Re: OS_GBPB 12 in a Wimp task Chris Johnson <chrisjohnson+news@spamcop.net> - 2012-03-15 20:26 +0000
Re: OS_GBPB 12 in a Wimp task Rick Murray <heyrickmail-usenet@yahoo.co.uk> - 2012-03-16 06:12 +0100
Re: OS_GBPB 12 in a Wimp task Matthew Phillips <spam2011m@yahoo.co.uk> - 2012-03-15 20:34 +0000
Re: OS_GBPB 12 in a Wimp task Alan Adams <alan@adamshome.org.uk> - 2012-03-15 21:04 +0000
Re: OS_GBPB 12 in a Wimp task Matthew Phillips <spam2011m@yahoo.co.uk> - 2012-03-16 00:17 +0000
Re: OS_GBPB 12 in a Wimp task Chris Johnson <chrisjohnson+news@spamcop.net> - 2012-03-10 23:58 +0000
Re: OS_GBPB 12 in a Wimp task Chris Johnson <chrisjohnson+news@spamcop.net> - 2012-03-11 10:43 +0000
Re: OS_GBPB 12 in a Wimp task jeff <jeffrey.a.doggett@gmail.com> - 2012-03-12 03:03 -0700
Re: OS_GBPB 12 in a Wimp task Chris Johnson <chrisjohnson+news@spamcop.net> - 2012-03-12 10:44 +0000
Re: OS_GBPB 12 in a Wimp task Matthew Phillips <spam2011m@yahoo.co.uk> - 2012-03-13 07:44 +0000
Re: OS_GBPB 12 in a Wimp task jeff <jeffrey.a.doggett@gmail.com> - 2012-03-13 03:06 -0700
Re: OS_GBPB 12 in a Wimp task druck <news@druck.org.uk> - 2012-03-07 10:08 +0000
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