Checksum: 24799
Path: utzoo!utgpu!woods
From: woods@gpu.utcs.toronto.edu (Greg Woods)
Date: Sun, 4-Sep-88 13:29:39 EDT
Message-ID: <1988Sep4.132939.26223@gpu.utcs.toronto.edu>
Organization: G. A. W. Consulting
Newsgroups: comp.unix.wizards
Subject: Re: terminfo
Summary: Terminfo documentation is actually quite good.
References: <508@altos86.UUCP> <8377@smoke.ARPA> <1553@mcgp1.UUCP> <8412@smoke.ARPA> <24729@bu-cs.BU.EDU>
Reply-To: woods@gpu.utcs.Toronto.EDU (Greg Woods)
Keywords: terminfo termcap curses documentation

In article <24729@bu-cs.BU.EDU> madd@bu-it.bu.edu (Jim Frost) writes:
> In article <8412@smoke.ARPA> gwyn@brl.arpa (Doug Gwyn (VLD/VMB) <gwyn>) writes:
> |In article <1553@mcgp1.UUCP> fst@mcgp1.UUCP (Skip Tavakkolian) writes:
> |-In article <8377@smoke.ARPA>, gwyn@smoke.ARPA (Doug Gwyn ) writes:
> |-> In article <508@altos86.UUCP> clp@altos86.UUCP (Chuck L. Peterson) writes:
> |-> >Why does terminfo exist?
> |-> Because termcap was too limited.
> |-Please explain.
> 
> My vote is against terminfo.  I found several problems with the
> supplied terminfo entries for the AT&T terminals (4435 I think)
> attached to 3b2's running SysVr2, as well as on the DMD graphics
> terminals.
> 
> I tried to fix the problems, but there was NO documentation on how to
> do it, and the terminfo information is not in a format such that it
> can be figured out in a reasonable amount of time.
> 
> [for termcap...]  The documentation was
> easy to find, but was also unnecessary in both cases.
> 
> Perhaps terminfo is functionally "better", but my experience has shown
> it to be much less "maintainable".  A broken "better" doesn't do much
> good.

I doubt you will ever find a perfect terminal database in any Unix
release, be it termcap or terminfo.  I certianly wouldn't go so far as
to call either "broken".  [ NOTE: the first SCO release of terminfo was
certianly broken.  The terminfo compiler generated files incompatible
with the terminfo library, but it has since been fixed. ]

Just because you knew how to edit and fix a termcap entry, but not a
terminfo entry, doesn't make terminfo a bad thing.

I have found the terminfo documentation quite satisfactory for
maintaining the database.  It is no more complex (in my opinion) than
that for termcap.

I'd guess that your difficulty with finding the appropriate terminfo
documentation has to do with the fact that the AT&T documentation is
organized _slightly_ differently from the BSD documentation.

DISCLAIMER:  I have not seen the documentation supplied with AT&T 3B2
System V Release 2.  I have a copy of the BSD 4.3 documents, the System
V Release 2.1 generic (AT&T/CBS/HRW) documents, and the System V Release
3.0 documents, and I have used (extensively) the SCO Xenix 2.2.1
documentation.

The terminfo library documentation that was supplied with Release 2.1
was little more than useless, but that has certianly been remedied in
Release 3.0.  In fact, the Release 3.0 Programmer's Guide is one of the
best curses tutorials I've seen.

My only complaint about terminfo is that it is HUGE.  The "bulls eye"
example from the programmers guide generates over 128 Kb of binary on a
386, from the 10 or so lines of code.  Including any input functionality
seems to double the binary again.  Terminfo on a 286 uses a tremendous
amount of stack space.  Maybe AT&T will get around to building a shared
library for curses....
-- 
						Greg Woods.

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