bin/143017: watch(8): fatal: cannot attach to tty

[Mark Johnston]

The following reply was made to PR bin/143017; it has been noted by GNATS.

From: Mark Johnston <markjdb at gmail.com>
To: Ed Schouten <ed at 80386.nl>
Cc: bug-followup at freebsd.org, dummy at smtp.ru
Subject: Re: bin/143017: watch(8): fatal: cannot attach to tty
Date: Mon, 12 Mar 2012 17:54:01 -0400

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 On Mon, Mar 12, 2012 at 5:52 PM, Mark Johnston <markjdb at gmail.com> wrote:
 > On Mon, Mar 12, 2012 at 5:27 PM, Ed Schouten <ed at 80386.nl> wrote:
 >> Sure, but in that case you can simply use isatty() to distinguish the
 >> special treatment. What I mean is that you can only call watch(8) by
 >> passing the TTY used on the command line.
 >
 > Ok, fair enough. I replaced opt_interactive with isatty(std_out)
 > checks. One check was unnecessary - the line with a FD_ISSET check. I
 > also added a check in unset_tty() so that the terminal doesn't break
 > if we bail with ^C.
 >
 > So the difference now is that in non-interactive mode, we're not
 > interested in stdin, and the tty has to be passed on the command line.
 >
 >> Also I see you've simplified the code that dynamically scales the input
 >> buffer size. Though I think that's a good idea, I do think we should
 >> increase BUF_SIZE to something higher. Setting it to 4 KB or something
 >> shouldn't harm, right?
 >
 > Yeah, good point. I've attached the regenerated patch.
 
 ...
 
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