Re: Re: Displaying Plane 1 characters (was Re: TV teletext)

From: Joan Aliprand (
Date: Wed Oct 14 1998 - 22:03:33 EDT

Frank da Cruz <> wrote:

>A good example
>that anybody can look at is Hebrew University's ALEPH bibliographic system,
>which (I believe) is used at every university in Israel, and also at the
>Jewish Theological Seminary of America in New York. The bidi issues are
>handled by the host software, transparently to the terminal or emulator, by
>cursor addressing and the like, so as long as the emulator has a Hebrew font
>and understands the protocols (ISO 2022 / VT320), Hebrew data entry and
>display are simple and straightforward.

Well, since today seems to be a day for mentioning products, let me put in
a word for RLG's implementation of Hebrew (and other scripts), also in an
ISO 2022 environment (in the standard USMARC bibliographic format, to be

The RLIN Terminal Software (our terminal emulator that runs under Windows)
handles the bidi movement. We supply fonts with the software (because the
USMARC character sets are not widely supported). We also support
non-spacing marks on characters (readable, but not at the level of

In RLIN, it's possible to mix any and all of Latin, Cyrilic, Hebrew and
Arabic scripts in any free text field in a record. [When I last saw ALEPH
it limited data in a field to Latin script plus one other, and AFAIK that's
still the case.]

RLIN is used by all the leading Hebraica libraries in the US. *

>As to Arabic, I'm sure it could work the same way, but from my limited
>understanding of the situation, there are rendering requirements beyond those
>of Hebrew that make display of Arabic (and probably Farsi, etc) in a
>rectangular grid of screen cells unacceptable to most readers, even though
>PC code pages have been available for use in DOS for many years.

RLG has also implemented Arabic script. To accommodate the longer letters,
we modified our terminal emulation software to handle characters one or two
cells wide. Character shaping is done "on the fly." We render the
lam-alif digraph from the component letters (entered and stored
individually). We also support joiner and non-joiner capability (after
Joe Becker -- I read his "Scientific American" and ACM papers).

And if you're wondering why we didn't use Unicode, well, Hebrew on RLIN was
released in 1988, and Arabic followed in 1991 (in the same month that
Volume 1 of "The Unicode Standard," Version 1.0 was published).

-- Joan Aliprand
   Senior Analyst
   The Research Libraries Group

* Frank: In your area, they are The New York Public Library, YIVO
  Institute for Jewish Research, Yeshiva University, Jewish Theological
  Seminary, Hebrew Union College (New York campus), New York University Law


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