Path: utzoo!attcan!uunet!mcvax!ukc!warwick!mirk
From: mirk@warwick.UUCP (Mike Taylor)
Newsgroups: comp.unix.questions
Subject: Re: tail -f
Message-ID: <876@ubu.warwick.UUCP>
Date: 11 Dec 88 17:48:40 GMT
References: <412@fedeva.UUCP> <10650037@hpisod2.HP.COM>
Sender: news@warwick.UUCP
Reply-To: mirk@emerald.UUCP (Mike Taylor)
Organization: Computer Science, Warwick University, UK
Lines: 13

>>>Can someone please tell me how 'tail -f' works? ...
>>In fact, it *does* do a busy loop while doing "read"s (not "stat"s) of
>>the file; it just sleeps 1 second between attempts to "read" ...
>I suppose it could use select(2)...

Not necessarily - select(2) is a Berkeleyism, I believe, so code written
using it is not portable to older Unices - Vanilla V7, for instance.
I must agree that it would be a far more elegant solution, though.
I am surprised that it hasn't been re-written for Berkeley systems.
______________________________________________________________________________
Mike Taylor - {Christ,M{athemat,us}ic}ian ...  Email to: mirk@uk.ac.warwick.cs
*** Unkle Mirk sez: "Gm F#7 Bb Cm->Gm->Eb->Gm F; Gm F#7 Bb C Eb C Bb Dm D" ***
------------------------------------------------------------------------------