Path: utzoo!attcan!uunet!husc6!bloom-beacon!tut.cis.ohio-state.edu!osupyr.mast.ohio-state.edu!vkr
From: vkr@osupyr.mast.ohio-state.edu (Vidhyanath K. Rao)
Newsgroups: comp.sys.amiga
Subject: PIPE device
Keywords: 256 byte lag
Message-ID: <1056@osupyr.mast.ohio-state.edu>
Date: 15 Nov 88 19:35:52 GMT
Reply-To: vkr@osupyr.mast.ohio-state.edu (Vidhyanath K. Rao)
Organization: Dept of Math, Ohio St U at Newark, Newark OH 43055
Lines: 27

I tried using the pipe device in the 1.3 package together with the tee
program from comp.sources.amiga. The `feature' also occurs with tee.rexx.

I have tried the following: Open two CLI's (or shells). In one do any of
the following:
   <some program> >Pipe:a  (I started with maple, but that shouldn't matter)
   copy * to pipe:a
   tee pipe:a
In the other window, do
   tee <pipe:a ram:x
There is a lag between what is supposed to go into the pipe: and when it
comes out. The later two options above indicate that the output from the
pipe comes in 256 byte blocks till end-of-file is reached. But the manual
says that pipe is transparant. C manuals say that `fopen' is unbuffered.
[Maple kernal is, I believe, written in Manx C]. I am lost as to what is
going on. Is there any way to have a tee that spills everything it has
recieved so far. I really need this to use Maple meaningfully.

Incidentally, in case this is pipe:'s fault, do other pipes behave in a
similar fashion? I was trying to put off buying WShell, but if it will
tee properly ...

Also the tee from comp.sources.amiga doesn't seems to handle EOF correctly.
The tee getting its input from the pipe doesn't know that it has got an
EOF if the feeder to the pipe is "tee pipe:<name>".

Thanks in advance for your help.