Messages in this thread | | | Date | Tue, 2 Apr 1996 00:40:28 -0500 (EST) | From | Kevin M Bealer <> | Subject | Re: strange disk activity [tail -f] |
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On Mon, 1 Apr 1996, Zefram wrote:
> >yep, "tail -f" reads (polls) the file every second, this in turn changes > >the atime field, and bdflush updates the inode and the superblock. > > There's a voice in my head saying "that should happen on open(2), not > read(2)". Am I just hallucinating? More to the point, why do we get > this repeated (and annoying) disk activity under 1.3.~80 but not > 1.2.x? Can the new bdflush be tuned to wait longer before flushing, > and if so, how? > > >might be a stupid question, but is there no way doing event based reads > >on files [selects and/or blocking reads at the end of the file] ? > > Not under Unix. > > -zefram
But couldn't you kludge it by
(use a script of course but pseudo C is easy to read :)
touch(/tmp/tempfile); while(1) { while(mod_date(/tmp/tempfile) < mod_date(/file/in/question)) { sleep(1); } clear(); touch(/tmp/tempfile); tail(/file/in/question); }
Or was the goal more frequent updates?
__kmb203@psu.edu_____________________________Debian/GNU__Linux__1.3.77___ To A Quick Young Fox: Why jog exquisite bulk, fond crazy vamp, Daft buxom jonquil, zephyr's gawky vice? Guy fed by work, quiz Jove's xanthic lamp -- Zow! Qualms by deja vu gyp fox-kin thrice. -- Lazy Dog
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