From: earle@poseur.JPL.NASA.GOV
Newsgroups: comp.windows.x
Date: 18 Jul 92 16:30 MDT
Subject: ANNOUNCEMENT: New version of X11-on
Nf-ID: #N:1992Jul18.123036.26328@elroy.jpl:76191303:001:7165
Nf-From: poseur.JPL.NASA.GOV!earle    Jul 18 16:30:00 1992


I have released a new version of my Perl ersatz "DocViewer" replacement
for enabling the use of AnswerBook on X11-only servers.  Version 2.0 now
supports AnswerBook 2.0 SMCC Version A, the version of AnswerBook released in
tandem with Solaris 2.0 SMCC Version A.  This new version follows below.
(It also lives on export.LCS.MIT.EDU in ~ftp/contrib/xdocviewer-2.0 with an
 accompaning README file.)

What "xdocviewer-2.0" is:
-------------------------

xdocviewer 2.0 is a Perl script that can be named "docviewer" and put into your
search $PATH ahead of the normal directory where the AnswerBook's version of
"docviewer" lives.  If this is done (it needs a small mod to your "answerbook"
shell script to work properly; see below), this script will get invoked when
the Navigator program goes to invoke the DocViewer to display the AnswerBook's
PostScript HyperText documentation.  This gets around the problem of using
AnswerBook on non-OpenWindows servers, such as plain X11 or X terminals, as
the script invokes a GhostScript previewer to display the document.

What "xdocviewer-2.0" is NOT:
-----------------------------

This script is most emphatically not a replacement for the "real" DocViewer
that comes with AnswerBook!  It's a "crippled crutch" to merely allow you to
use the Navigator and get a PostScript document up on your screen.  You lose
the HyperText capability right away, and every document you choose (or
manually double-click on in the Navigator) results in a new GhostScript
previewer process being run, as the Navigator and GhostScript previewers don't
talk to one another.  You also can't go past the end of a document (or, vice
versa, go back before the start of one) and have the viewer automatically
"know" how to get to the next document (or the previous document).  Etc., etc.

The problem of having the "real" DocViewer work on plain X11-only servers is
being dealt with by the AnswerBook folks.  In the meantime, try this out and
see if it is useful to you.  (I use it daily, as the AnswerBook is too useful
a tool to not be able to use it, no matter how limited a fashion it may be.)

Prerequisites to use xdocviewer-2.0:
------------------------------------

- You need Perl (-:  I use 4.0 pl 19; I suspect 4.0 pl 35 will work fine.

- You need GhostScript.  2.4.1 is supported/preferred.  aeneas.MIT.EDU has it.

- You need a GhostScript previewer.  GhostView 1.3 and GSpreview 2.1 are the
  supported previewers currently (those versions supply the "-page" option
  which is needed for this to work).  Check on export or aeneas for these.

- You need the XView shared libraries - libxview, libolgx - installed somewhere
  that's accessible, either /usr/lib or /usr/local/lib or someplace accessible
  via LD_LIBRARY_PATH.  You can either build those libraries from the XView 3.0
  distribution with R5, or else nick them from your favorite local OpenWindows
  $OPENWINHOME/lib directory.  The Navigator needs these shared libraries.

- You need a BOOKINFO file (default /etc/bookinfo).  With the AnswerBook 1.3
  release CD-ROM, you could create one by running the "answerbook_demo" script
  and hand-editting the /tmp/bookinfo file it emits.  The Solaris 2.0 AB will
  create a temporary bookinfo file on the fly and use that; e.g.:

poseur:2:1278 % head -2 /tmp/bookinfo*
SUNWab_2_1:../../../../NonReloc_SUNWabook/_data:../../PostScriptDEST:../../PostScriptDEST/sr_index/SUNWab_2_1:Solaris 2.0 AnswerBook
ABGTOUR:../../../../NonReloc_SUNWabook/_data:../../PostScriptDEST::Solaris 2.0 AnswerBook

(These caveats are repeated in the comments in the script below.)

Please address all bug reports/questions/comments to me:

Enjoy,

	- Greg Earle
	  Sun Microsystems, Inc. - Los Angeles
	  JPL on-site Software Support Engineer
	  earle@poseur.JPL.NASA.GOV, earle@Sun.COM

------------------------------ >8  Cut here  8< ------------------------------
#!/usr/local/bin/perl
#
#	@(#)docviewer.sh 2.0 92/07/17 SMI

# Display AnswerBook document pages using ndbm database keys and data

# If you don't have "perl", too bad.  Go get it.

# This is Version 1.0 (meaning, it's the first thing that I got to work)

# Revision history:
#
# 1.0Alpha	92/06/06	Initial release.  First thing I got to work
# 1.0Beta	92/06/07	Changed several things thanks to Wayne Thompson
#				All changes due to my own Perl brain-death
# 1.0		92/06/08	BOOKINFO and GSVIEWER now have default values
# 2.0		92/07/17	Fixed bugs that showed up when attempting to
#				use with Solaris 2.0 AnswerBook 2.0 - things
#				were not quite as they seemed.  Code is now
#				more general and supports AB 2.0
#
# Requirements:

# Needs the XView libraries installed (libxview.s[oa].3.x and libolgx.s[oa].3.x)
# somewhere reachable, either in /usr/lib or /usr/local/lib or in your X11 R[45]
# lib directory or ... etc. - if the latter, e.g. $OPENWINHOME/lib, you'll
# probably have to set the LD_LIBRARY_PATH variable to point to that directory
# in order to pick the libraries up.  Otherwise, the Navigator program won't
# come up.

# Needs BOOKINFO set (default is /etc/bookinfo) either in the environment or in
# the "answerbook" script so it can find where the AnswerBook data files are

# Needs a new environment variable named GSVIEWER set to your preferred
# GhostScript previewer that's available in your $PATH - common choices are
# "ghostview" (requires version 1.3 to work!) or "gspreview" (requires 2.1)
# Default is "gspreview" (I flipped a coin (-: )

# Warning: normal "answerbook" script puts DocViewer directory at the front of
# the search path, so to get this version first, I recommend changing it; e.g.:
#
# *** /cdrom/AnswerBook1.3/answerbook     Thu Dec 19 11:06:28 1991
# --- /usr/local/bin/answerbook   Sat Jun  6 04:20:29 1992
# ***************
# *** 49,53 ****
#   echo $PATH | fgrep -s  "$dvbin" ||
#   {
# !       PATH="$dvbin:$PATH"
#   }
#
# --- 60,65 ----
#   echo $PATH | fgrep -s  "$dvbin" ||
#   {
# ! #     PATH="$dvbin:$PATH"
# !       PATH="$PATH:$dvbin"
#   }

sub getbookinfo {

	$ENV{'BOOKINFO'} = $ENV{'BOOKINFO'} || "/etc/bookinfo";

	open(BOOKINFO, $ENV{'BOOKINFO'}) || die "Can't open bookinfo file!\n";

	while (<BOOKINFO>) {
		($db, $dbpathhead, $pspathhead) = split(/:/);
		if ($db eq $dbname) {
			return $dbpathhead;
		}
	}
	close(BOOKINFO);
}

$ENV{'GSVIEWER'} = $ENV{'GSVIEWER'} || "gspreview";

# Kill off any running ghostview/gspreview/whatever processes

open(PS, "/bin/ps -xc 2>&1 |");
while (<PS>) {
	if (/$ENV{'GSVIEWER'}/) {
		split(' ');
		push(@pids, $_[0]);
	}
}
close(PS);
$nkilled = kill("SIGTERM", @pids);

($dbname) = ((join($",@ARGV)) =~ /^.*<(\S+)>/);
($dbtoken) = (join('', '<', $dbname, '>', ((join($",@ARGV)) =~ /^.*>(\S+)/)));

$dbhead = &getbookinfo();

$dbpath = "$dbhead/$dbname";
$pspath = "$pspathhead/$dbname";

dbmopen(ABDB, $dbpath, undef) || die "can't dbmopen AnswerBook database";

while (($key, $val) = each %ABDB) {
	local ($data, $datum);

	$datum = unpack('@8A*', $key);
	@data = split(/:/, $val);

	$page = @data[$#data];
	$doc = @data[$#data-1];
	last if (($datum eq $ARGV[$#ARGV]) || ($datum eq $dbtoken));
}

dbmclose(ABDB);
exec($ENV{GSVIEWER}, '-page', $page, "$pspath/$doc");

Newsgroups: comp.windows.x