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Mail Archives: djgpp-workers/2001/07/31/10:44:32

From: "Mark E." <snowball3 AT bigfoot DOT com>
To: djgpp-workers AT delorie DOT com
Date: Tue, 31 Jul 2001 10:44:12 -0400
MIME-Version: 1.0
Subject: Re: termios flag to control ecma-48
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Reply-To: djgpp-workers AT delorie DOT com

> So the relevant 
> question is: what is the practical consequence of raw output, and what 
> commands does it affect?

The evidence I've seen suggests that the escape commands should be active. 
Cygwin and Linux act this way. The gnu termcap documentation in the 
"initialization for use of termcap" section distinguishes between output 
commands and output processing:

Before starting to output commands to a terminal using termcap, an 
application program should do two things: 

      Initialize various global variables which termcap library output 
functions refer to. These include PC and ospeed for padding (see Output 
Padding) and UP and BC for cursor motion (see tgoto). 
      Tell the kernel to turn off alteration and padding of horizontal-tab 
characters sent to the terminal. 

      To turn off output processing [berkeley method snipped] In POSIX or 
System V, you must clear the bit named OPOST. Refer to the system 
documentation for details. 

This distinction matches what cygwin and linux do. The merge of the two tty 
write function has the tab character work the same between raw and cooked 
mode.

The excerpt casts doubt on the current handling of the tab char by the tty 
writer. It's output  the same whether in raw or cooked mode. Perhaps tab in 
raw mode should just go directly to the tab stop instead of spacing its way 
there? I don't think going back to the previous raw mode behavior of sending 
the tab to __direct_output is good because it just prints a graphics 
character.

Mark

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