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Cc: freebsd-hackers@freebsd.org
Subject: Re: preventing FIFO from EOF
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rihad schrieb:
> $ mkfifo /var/tmp/foo
> $ buffer -i /var/tmp/foo                    # misc/buffer
> # in another console:
> $ echo hi > /var/tmp/foo
> 
> buffer prints hi and exits. I want it to keep reading and printing 
> indefinitely.
> 
> Further experimentation revealed that I need two writers: one dummy 
> writer that just keeps /var/tmp/foo open for writing, and the other 
> doing the "real work". This way buffer wouldn't exit. But how to emulate 
> the dummy writer? It itself needs to block on something to keep 
> /var/tmp/foo open. Any clean way to do this in shell? Maybe the solution 
> is quite simple but isn't at the tip of my tongue.

Maybe "tail -f" is what you are looking for.