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From: mre@beatnix.UUCP (Mike Eisler)
Newsgroups: comp.unix.questions
Subject: Re: 'peeking' in on a pipe
Message-ID: <2830@elxsi.UUCP>
Date: 14 Jul 89 01:05:43 GMT
References: <6.24B47361@seaeast.WA.COM> <193@safn2.UUCP>
Sender: news@elxsi.UUCP
Reply-To: mre@beatnix.UUCP (Mike Eisler)
Organization: ELXSI Super Computers, San Jose
Lines: 14

In article <6.24B47361@seaeast.WA.COM>, Tim.Evans@f112.n138.z1.WA.COM (Tim Evans) writes:
> I would like to 'peek' in on a pipe, to see what is happening in it, WHILE
> IT EXECUTES. I tried something like this, but no luck:
>  
>   some_stuff | tee `tty` | more_stuff

Try
	 some_stuff | tee /dev/tty | more_stuff

 ... | tee `tty` | more_stuff fails because tty(1) calls ttyname(3) to find

terminal name with file descriptor 0 as its argument. Fd 0 is a pipe
when tee is used inside a pipeline.
	uunet!elxsi!mre