From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dan Cross <cross@math.psu.edu>
Message-Id: <200109051422.KAA02761@augusta.math.psu.edu>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] weird print(2) problems...
In-Reply-To: <20010904190825.3180.qmail@f.bio.cse.psu.edu>
References: <cross@math.psu.edu>
Cc:
Date: Wed,  5 Sep 2001 10:22:18 -0400
Topicbox-Message-UUID: e9f0ea72-eac9-11e9-9e20-41e7f4b1d025

In article <20010904190825.3180.qmail@f.bio.cse.psu.edu> you write:
>Hm.  Pipes in Plan 9 preserve write boundaries, right?  Print is probably
>sending a zero length write, and confusing programs that interpret it
>as eof.

Hmm, that seems plausible.  It's also rather annoying; it seems to me
that if write(2) sees a zero length argument, it should consider that a
nop and return.  But then it seems that that would break some weird
semantic somewhere (``Any write will update a timestamp; except for
zero length writes, which are ignored.'' ``Dude, that's broken.'')

Is there an elegant solution (other than ``don't do print("");'',
since that might really mean ``don't do,

	read(0, str, 128);
	trimwhitespace(str);
	print("%s", str);

where the only thing read is a blank line or something.'')?

	- Dan C.