Re: [Announce] GIT v1.5.0-rc2

> [ Added "less" author Mark Nudelman to Cc: ]
> 
> On Tue, 23 Jan 2007, Bill Lear wrote:
>> I can't seem to get this to work, no matter what I do, using the
>> latest 1.5.0-rc2 code.  I have the environment variables LESS, PAGER,
>> PAGER_FLAGS, and I can't seem to get 'git diff' to not plough through
>> my screen each time it is run, no matter the combinations...  Could
>> someone post the magic?
> 
> I think "less" is actually seriously buggy with -F.
> 
> There are two bugs:
> 
>  - it will always screw up the screen and move to the end. It does this 
>    even if you use -FX which should disable any init sequences, so it's 
>    not about that problem.
> 
>  - if you resize the terminal while less is waiting for input, less
>    will exit entirely without even showing the output. This is very
>    noticeable if you do something like "git diff" on a big and cold-cache 
>    tree and git takes a few seconds to think, and then you resize the 
>    window while it's preparing. Boom. No output AT ALL.
> 
> Both bugs are easily seen with this simple command line
> 
> 	clear ; (sleep 5 ; echo Hello) | less -F
> 
> where you would EXPECT that the "Hello" would show up at the first line of 
> the screen (since we cleared the screen and moved to the top left corner), 
> but in fact it doesn't.
> 
> And try resizing the terminal to make it bigger during the five-second 
> pause, and now you'll see less not show the "Hello" at _all_. It's just 
> gone (this is true even if the output was _more_ than a screen: try with
> 
> 	(sleep 10 ; yes ) | less -F
> 
> and resize the screen, and it will exit silently after 10 seconds - never 
> showing any output at all! Even though the output is obviously bigger than 
> a screen..
> 
> Tested with Kterm, gnome-terminal and xterm. They all behave the same for 
> me.
> 
> I don't know exactly what the bug is, but I find the "eof" handling very
> confusing in the less sources. It makes me suspect that there is something 
> that gets confused by the partial read, sets EOF (since we're on the last 
> line), and then thinks that it should quit, since EOF is set.
> 
> I dunno. Mark?
> 
> 		Linus
>