From mboxrd@z Thu Jan  1 00:00:00 1970
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In-Reply-To: <1302e45ee0d510249bd57bef3594d66c@quanstro.net>
References: <dd6fe68a0904071848v3bbd48c1n9a3e8f02606d129d@mail.gmail.com>
	 <1302e45ee0d510249bd57bef3594d66c@quanstro.net>
Date: Wed,  8 Apr 2009 13:33:50 +1000
Message-ID: <dd6fe68a0904072033g772a07dmaa16b7963e3ad207@mail.gmail.com>
Subject: Re: [9fans] self inflicted gunshot wound
From: Russ Cox <rsc@swtch.com>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
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> acid: *(*plumbpackattr:s\s)
> filetype=3Dmail sender=3Dxxxx@xxxx.xxx length=3D8749 mailtype=3Ddelete
> date=3D'Sun Mar4de7153cecd4a9b45aead1clfs
> digest=3Daff98fb56526d94ab768adbc93d12d989a11ed53

> several were waiting on something else to happen; they were
> sleeping waiting for an exclusive-open file. =C2=A0the only reason
> i mentioned it is that may have been 5 minutes between the
> time that plumber tried to write the message and when it
> could be delivered.

aha.  plumbunpackattr is also using attrbuf.
that explains it.  a new plumbing message came
in at the same time an old one was being
delivered.  this can only happen if a reader
gets behind and is catching up while new
messages are still coming in.

i would put a lock around the use of attrbuf
in both plumbpackattr and plumbunpackattr.

russ