Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!rutgers!mit-eddie!uw-beaver!teknowledge-vaxc!sri-unix!quintus!pds
From: pds@quintus.uucp (Peter Schachte)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Standardization
Keywords: Menus
Message-ID: <574@quintus.UUCP>
Date: 25 Oct 88 22:41:25 GMT
References: <1314@nmtsun.nmt.edu> <2287@cadovax.UUCP> <221@antares.UUCP> <5092@cbmvax.UUCP>
Sender: news@quintus.UUCP
Reply-To: pds@quintus.UUCP (Peter Schachte)
Organization: Quintus Computer Systems, Inc.
Lines: 37

In article <5092@cbmvax.UUCP> jesup@cbmvax.UUCP (Randell Jesup) writes:
>In article <221@antares.UUCP> jms@antares.UUCP (joe smith) writes:
that there should be a way for a program to signal that a directory has
changed so a program that display the dir notices the change.  (correct
me if I misunderstood).

>	Just do an Examine, and compare the change data for the
>directory with the old change date: if they're different, something may
>have changed.  If not, not problem.

This would work fine, except WHEN do you check?  You certainly check
when you go to display the directory.  But suppose you're displaying the
directory when a file is added, and you want the display to be updated
right away.  Does your program check the change date for the directory
every few seconds just to see if something has changed?  Wouldn't this
create a lot of useless disk accesses?

The problem with allowing programs to signal when a directory has
changed is that lots of (most) programs wouldn't do it, so the
directory displays would still be wrong.  This needs to be something
the file system does.  Unless....

Couldn't this be accomplished by putting a process in the "food chain"
before the disk (and RAM:, RAD:, etc.)  devices that watch for file
creation and deletion packets, and send the appropriate messages to any
programs that are displaying info about that directory.  Can this be
done?  This is something someone outside of DOGS could do (unlike
changing the file system).  If done right, C= might "bless" it, and use
it to keep Workbench windows up-to-date.

Or is something like this planned for the 1.4 Workbench upgrade?  If
so, I hope it will be done in such a way that file requesters etc. will
be able to use it too.

-Peter Schachte				"Clean water?  I'm for clean water."
pds@quintus.uucp				-George Bush
..!sun!quintus!pds