[TUHS] Anyone know what a LANTERN is?

[TUHS] Anyone know what a LANTERN is?

[Random832]

There is a character in the terminfo/curses alternate character set,
ACS_LANTERN, which is mapped to "i" in the VT100 alternate grapical
character set. This character is, in fact, on a real VT100/VT220 (and
therefore in most modern terminal emulators that support the full ACS),
"VT" (in 'control character picture' format, along with HT FF CR LF NL).
The ASCII mapping uses "#", and some CP437/etc mappings map it to the
double box drawing intersection character.

Was there ever a real 'lantern' character? The manpage mentions "some
characters from the AT&T 4410v1 added". What did it look like?

[TUHS] Anyone know what a LANTERN is?

[Paul Winalski]

I don't think there wasn't any character called 'lantern' on the real
VT100.  As you said, the code displays as the "VT" glyph when the DEC
Special Graphics character set is selected.  The VT100 User's Manual
doesn't mention 'lantern' anywhere.

-Paul W.

On 7/27/17, Random832 <random832 at fastmail.com> wrote:
> There is a character in the terminfo/curses alternate character set,
> ACS_LANTERN, which is mapped to "i" in the VT100 alternate grapical
> character set. This character is, in fact, on a real VT100/VT220 (and
> therefore in most modern terminal emulators that support the full ACS),
> "VT" (in 'control character picture' format, along with HT FF CR LF NL).
> The ASCII mapping uses "#", and some CP437/etc mappings map it to the
> double box drawing intersection character.
>
> Was there ever a real 'lantern' character? The manpage mentions "some
> characters from the AT&T 4410v1 added". What did it look like?
>

[TUHS] Anyone know what a LANTERN is?

[Steve Nickolas]

On Thu, 27 Jul 2017, Random832 wrote:

> There is a character in the terminfo/curses alternate character set,
> ACS_LANTERN, which is mapped to "i" in the VT100 alternate grapical
> character set. This character is, in fact, on a real VT100/VT220 (and
> therefore in most modern terminal emulators that support the full ACS),
> "VT" (in 'control character picture' format, along with HT FF CR LF NL).
> The ASCII mapping uses "#", and some CP437/etc mappings map it to the
> double box drawing intersection character.
>
> Was there ever a real 'lantern' character? The manpage mentions "some
> characters from the AT&T 4410v1 added". What did it look like?
>

I thought it referred to character 127 in CP437?

-uso.

[TUHS] Anyone know what a LANTERN is?

[Paul Ruizendaal]

> Message: 1
> Date: Thu, 27 Jul 2017 11:58:38 -0400
> From: Random832 <random832 at fastmail.com>
> To: tuhs at minnie.tuhs.org
> Subject: [TUHS] Anyone know what a LANTERN is?
> Message-ID:
> 	<1501171118.69633.1054588920.11864815 at webmail.messagingengine.com>
> Content-Type: text/plain; charset="utf-8"
> 
> There is a character in the terminfo/curses alternate character set,
> ACS_LANTERN, which is mapped to "i" in the VT100 alternate grapical
> character set. This character is, in fact, on a real VT100/VT220 (and
> therefore in most modern terminal emulators that support the full ACS),
> "VT" (in 'control character picture' format, along with HT FF CR LF NL).
> The ASCII mapping uses "#", and some CP437/etc mappings map it to the
> double box drawing intersection character.
> 
> Was there ever a real 'lantern' character? The manpage mentions "some
> characters from the AT&T 4410v1 added". What did it look like?

There's two references in the termcap manpages:
http://invisible-island.net/ncurses/man/terminfo.5.html
and
http://invisible-island.net/ncurses/man/curs_add_wch.3x.html

The second link mentions that the AT&T 4410 terminal added this glyph in the location of the VT100 VT glyph. Apparently what it looked like is lost, unless someone finds a detailed 4410 manual (or has a working one in the attic).

[TUHS] Anyone know what a LANTERN is?

[Alan D. Salewski]

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On 2017-07-28 13:46:40, Paul Ruizendaal spake thus:
> 
> > Message: 1
> > Date: Thu, 27 Jul 2017 11:58:38 -0400
> > From: Random832 <random832 at fastmail.com>
> > To: tuhs at minnie.tuhs.org
> > Subject: [TUHS] Anyone know what a LANTERN is?
> > Message-ID:
> > 	<1501171118.69633.1054588920.11864815 at webmail.messagingengine.com>
> > Content-Type: text/plain; charset="utf-8"
> > 
> > There is a character in the terminfo/curses alternate character set,
> > ACS_LANTERN, which is mapped to "i" in the VT100 alternate grapical
> > character set. This character is, in fact, on a real VT100/VT220 (and
> > therefore in most modern terminal emulators that support the full ACS),
> > "VT" (in 'control character picture' format, along with HT FF CR LF NL).
> > The ASCII mapping uses "#", and some CP437/etc mappings map it to the
> > double box drawing intersection character.
> > 
> > Was there ever a real 'lantern' character? The manpage mentions "some
> > characters from the AT&T 4410v1 added". What did it look like?
> 
> There's two references in the termcap manpages:
> http://invisible-island.net/ncurses/man/terminfo.5.html
> and
> http://invisible-island.net/ncurses/man/curs_add_wch.3x.html
> 
> The second link mentions that the AT&T 4410 terminal added this glyph in the location of the VT100 VT glyph. Apparently what it looked like is lost, unless someone finds a detailed 4410 manual (or has a working one in the attic).
> 

The wecho_wchar(3ncurses) page[0] on my Debian box happens to mention
the following[1] in a discussion about incorporating Unicode support:

<quote>
    ·   The lantern is a special case.  It originated with  the  AT&T  4410
        terminal  in the early 1980s.  There is no accessible documentation
        depicting the lantern symbol on the AT&T terminal.

        Lacking documentation, most readers assume that a storm lantern was
        intended.  But there are several possibilities, all with problems.

        Unicode  6.0  (2010)  does provide two lantern symbols: U+1F383 and
        U+1F3EE.  Those were not available  in  2002,  and  are  irrelevant
        since  they  lie  outside the BMP and as a result are not generally
        available in terminals.  They are not storm lanterns, in any case.

        Most storm lanterns have a tapering glass chimney (to guard against
        tipping); some have a wire grid protecting the chimney.

        For  the  tapering  appearance, ☃ U+2603 was adequate.  In use on a
        terminal, no one can tell what the image represents.  Unicode calls
        it a snowman.

        Others  have suggested these alternatives: § U+00A7 (section mark),
        Θ U+0398 (theta), Φ U+03A6 (phi), δ U+03B4 (delta), ⌧ U+2327 (x  in
        a  rectangle), ╬ U+256C (forms double vertical and horizontal), and
        ☒ U+2612 (ballot box with x).
</quote>




[0] From a version 6.0+20170715-2 of the 'ncurses-doc' package:

        $ man -aw wecho_wchar
        /usr/share/man/man3/add_wch.3ncurses.gz

        $ dpkg -S $(man -aw wecho_wchar)
        ncurses-doc: /usr/share/man/man3/add_wch.3ncurses.gz

        $ dpkg -l ncurses-doc | grep '^i'
        ii  ncurses-doc    6.0+20170715-2    all    developer's guide and documentation for ncurses


[1] Which, AFAICT is a recent addition to the page, documented by the
    below NEWS file entry:

    <quote src="http://invisible-island.net/ncurses/NEWS.html#index-t20170506">
        20170506
    ...
                + improve discussion of line-drawing characters in curs_add_wch.3x
                  (prompted by discussion with Lorinczy Zsigmond).
    ...
    </quote>