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Date: Mon, 15 Sep 1997 19:22:38 +1000
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199709150922.TAA08480@godzilla.zeta.org.au>
To: luigi@labinfo.iet.unipi.it, mike@smith.net.au
Subject: Re: cvs commit: src/sys/i386/isa/snd - Imported sources
Cc: cvs-all@FreeBSD.ORG, cvs-committers@FreeBSD.ORG, cvs-sys@FreeBSD.ORG,
        jmg@FreeBSD.ORG
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>I am trying to figure out the difference between select and poll,
>it does not appear to be anything substantial, i.e. just a change
>in arguments in ("events" instead of "rw") and out ("revents"
>instead of 0/1). Is there any documentation somewhere ?

There are many examples in *.c.

>On passing, it seems that sequences like the following (from
>pcaudio.c, a similar thing is in asc.c) would be much easier to
>read if replaced by selrecord(p, &pca_status.wsel ).
>
>	if (pca_status.wsel.si_pid &&
>		    (p1=pfind(pca_status.wsel.si_pid))
>		    && p1->p_wchan == (caddr_t)&selwait)
>		pca_status.wsel.si_flags = SI_COLL;
>	else
>		pca_status.wsel.si_pid = p->p_pid;

selrecord() is a BSD4.4Lite interface.  The above drivers apparently
haven't been converted to it yet.

Bruce