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Date: Thu, 29 Jan 2009 19:53:37 +0000
From: Andy Koppe <andy DOT koppe AT gmail DOT com>
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Subject: Re: MinTTY feature? Or bug?
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Lee D. Rothstein wrote:
> Interesting feature or bug of MinTTY that does not obtain with any other
> terminal emulator with which I'm familiar.
> 
> To wit:
> 
> If you have a running synchronous script or command to the screen and you
> type ^l (Ctrl-l) it will immediately clear the screen before the ongoing
> command terminates.
> 
> My feeling is that it doesn't matter, but that the behavior is different
> from other virtual terminals.

I've had a look at this: it's a feature that MinTTY inherited from 
PuTTY. PuTTY emulates features of a whole range of terminals from VT100 
through to VT510, and also the so-called 'SCO ANSI' (from before SCO 
became a dirty word).

Apparently the latter interprets the echoed ^L as an actual form feed, 
whereas all the others just do a linefeed. (There's a separate sequence 
for clearing the screen, which bash sends when it sees a ^L being typed.)

The default compatibility setting includes 'SCO ANSI', hence the 
behaviour you're seeing. I'll take it out in the next release.

Andy

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