Bug 76863

Summary: Bug in terminfo el1 - ESC [ 1 K sequence.
Product: [Retired] Red Hat Linux Reporter: Sam Varshavchik <mrsam>
Component: vteAssignee: Nalin Dahyabhai <nalin>
Status: CLOSED RAWHIDE QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: 8.0CC: mitr
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Hardware: i386   
OS: Linux   
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Fixed In Version: Doc Type: Bug Fix
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Last Closed: 2003-01-09 22:18:24 UTC Type: ---
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Description Sam Varshavchik 2002-10-28 12:19:55 UTC
Description of Problem:

Reproducible display corruption in terminfo application as a result of
gnome-terminal responding to ESC [ 1 K (terminfo el1) by clearing from the
beginning of the line up to but not including the current cursor position.  The
terminfo el1 sequence should clear from the beginning of the line up to and
including the current cursor position.


Version-Release number of selected component (if applicable):

2.0.1-5

How Reproducible:

Always

Steps to Reproduce:

$ echo -e 'aaaabc\b\E[1K'

Actual Results:

     c

Expected Results:

blank line

Additional Information:
	
Date: Sun, 27 Oct 2002 19:15:52 -0500 (EST)
From: Thomas E. Dickey <dickey.com>
To: Sam Varshavchik <mrsam>
Cc: bug-ncurses
Subject: Re: terminfo el1 sequence semantics.

On Sun, 27 Oct 2002, Sam Varshavchik wrote:

> I'm trying to track down the reason for some occasional screen garbage from
> an application that uses ncurses 5.2 and runs under gnome terminal 2.0.1
>
> The garbage is reproducible. What I've been able to determine is this:
>
> * gnome-terminal uses TERM=xterm

(rofl ;-)

> * the culprit is the following terminfo sequence:
>
>   clr_bol                       el1        cb        Clear to beginning
>                                                      of line
>
> * terminfo specifies '\E[1K' for 'el1'.
>
> * If I set el1 to \s\b\E[1K for xterm, the corruption I'm observing goes
>  away.
>
> Based on that, it appears to me that:
>
> * ncurses expects el1 to clear from the beginning of the line up to, and
>  including the current cursor column.

which happens to be consistent with vt100, etc.  (double-checked just now
by referring to my vt300 manual).

> * gnome terminal responds to \E[1K by clearing from the beginning of the
>  line up to, but not including, the current cursor column.  For example:
>
> $ echo -e 'aaaabc\b\E[1K'
>     c
>
> So, who's right?

It looks like a bug in gnome-terminal

Comment 1 Nalin Dahyabhai 2003-01-09 22:18:24 UTC
Fixed in Raw Hide.