Re: [Monotone-devel] making opendiff wait

[William Uther]

On 21/02/2007, at 9:03 PM, Nathaniel Smith wrote:

> On Wed, Feb 21, 2007 at 05:14:12PM +1100, William Uther wrote:
> > Hi all,
> >
> >   At the moment mtn can use the 'opendiff' command on a mac for
> > merging.  By default this doesn't wait till you're done merging
> > before it continues, so you have a special hook that asks for <enter>
> > before continuing.  This is annoying.  :)
> >
> >   It turns out that opendiff does wait if you pipe its output
> > somewhere (although it waits until quit, not until window close).
> > This is a little script I use:
> >
> > #! /bin/zsh
> > `/usr/bin/opendiff address@hidden
>
> Wait, _what_?  That makes like.... no sense whatsoever.

I know.  I found it on the web.  I assumed there was an isatty check  
there somewhere.

opendiff | more

also works.

> If you google for opendiff, basically every hit is someone trying to
> figure out how to achieve this result, and I'm told that apple's
> internal bug tracker has had a bug open requesting this for 6+ years.
>
> How the heck did you discover this?

Web search.  There was a blog at MIT that had it.

> What's the actual detail needed to trigger this, do you think?
> isatty(1) returning false?

That's what I thought.  What is weird is that I tried to make this  
work using my shiny new spawn_pipe() lua hook, and couldn't.

> Does it give a useful exit code?

Haven't checked.  I suspect the `` are going to cause problems for  
the exit code.  Might want to try the |more trick instead.

> What happens if the user already has FileMerge.app running?  I assume
> they have to exit out of it entirely?  (Not that this is likely to
> come up much.)

Again, haven't tried.  Given that you have to exit entirely for the  
normal use, I assume the same holds true if it was already open.

BTW, if you run 'strings opendiff' you'll see a '-wait' option.  If  
you use it, then opendiff waits.  The problem is that it never  
unwaits :).  Something strange is going on.

Be well,

Will         :-}