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    Thanks, both -t or -tt works. But I still can't understand real reason of this: say, when I call shell remotely and close the connection, shell is terminated. But tail -f is not. Of course I have already read about -t option in man ssh, but it didn't help much. It seems I don't understand some generics, and I'd be happy if you suggest some docs to read about it, or probably explain it yourself. Thanks! Commented Jun 1, 2014 at 16:06
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    @DmitryFrank My understanding is this: If the connection breaks then sshd sends a SIGHUP. But where no terminal is there can be no terminal connection hangup... Commented Jun 1, 2014 at 16:29
  • Thanks, I will read about SIGHUP and other signals, still know almost nothing about it. Commented Jun 1, 2014 at 16:35
  • fyi: I just tried to run tail -f, then I've opened htop and sent SIGHUP to it (by pressing F9 -> 1 -> Enter), and tail -f is terminated! So, reason should be some different.. Commented Jun 1, 2014 at 17:59
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    @DmitryFrank You have misunderstood the problem. The problem is not that tail would not react to SIGHUP. The problem is that SIGHUP is **not sent` to tail without a pseudo terminal. You can see that by attaching strace to tail in both cases. Commented Jun 1, 2014 at 18:41