#!/bin/sh # -*- perl -*-
# $Id$

# tcsh.man2html, Dave Schweisguth <dcs@proton.chem.yale.edu>
#
# Notes:
#
# Always puts all files in the directory tcsh.html, creating it if necessary.
# tcsh.html/top.html is the entry point, and tcsh.html/index.html is a symlink
# to tcsh.html/top.html so one needn't specify a file at all if working through
# a typically configured server.
#
# Designed for tcsh manpage. Guaranteed not to work on manpages not written
# in the exact same style of nroff -man, i.e. any other manpage.
#
# Makes links FROM items which are both a) in particular sections (see
# Configuration) and b) marked with .B or .I. Makes links TO items which
# are marked with \fB ... \fR or \fI ... \fR.
#
# Designed with X Mosaic in mind and tested lightly with lynx. I've punted on
# HTML's lack of a .PD equivalent and lynx's different <menu> handling.

# Emulate #!/usr/local/bin/perl on systems without #!

eval '(exit $?0)' && eval 'exec perl -S $0 ${1+"$@"}'
& eval 'exec perl -S $0 $argv:q' if 0;

### Constants

# Setup

($whatami = $0)	=~ s|.*/||;	# `basename $0`
$isatty		= -t STDIN;

# Configuration

$index		= 0;		# Don't make a searchable index CGI script
$cgibin		= 0;		# Look for $cgifile in $dir, not $cgibindir
$shortfiles	= 0;		# Use long filenames
$single		= 0;		# Make single page instead of top and sections

$host		= '';		# host:port part of server URL ***
$updir		= '';		# Directories between $host and $dir ***
$dir		= 'tcsh';	# Directory in which to put the pieces *
$cgifile	= 'tcsh.cgi';	# CGI script name **
$cgibindir	= 'cgi-bin';	# CGI directory ***
$headerfile	= 'header';	# HTML file for initial comments *
$indexfile	= 'index';	# Symlink to $topfile *
$listsfile	= 'lists';	# Mailing list description HTML file *	
$outfile	= 'tcsh.man';	# Default input file and copy of input file
$script		= $whatami;	# Copy of script; filename length must be OK
$topfile	= 'top';	# Top-level HTML file *

# *   .htm or .html suffix added later
# **  Only used with -i or -c
# *** Only used with -c

# Sections to inline in the top page

%inline_me	= ('NAME',	1,
		   'SYNOPSIS',	1);

# Sections in which to put name anchors and the font in which to look for
# links to those anchors

%link_me	= ('Editor commands',		'I',
		   'Builtin commands',		'I',
		   'Special aliases',		'I',
		   'Special shell variables',	'B',
		   'ENVIRONMENT',		'B',
		   'FILES',			'I');

### Arguments and error-checking

# Parse args

while ($#ARGV > -1 && (($first, $rest) = ($ARGV[0] =~ /^-(.)(.*)/))) {
    # Perl 5 lossage alert
    if ($first =~ /[CdDGh]/) {	# Switches with arguments
    	shift;
    	$arg = $rest ne '' ? $rest : $ARGV[0] ne '' ? shift :
      	    &usage("$whatami: -$first requires an argument.\n");
    } elsif ($rest ne '') {
    	$ARGV[0] = "-$rest";
    } else {
	shift;
    }
    if	  ($first eq '1')   { $single = 1; }
    elsif ($first eq 'c')   { $cgibin = 1; }
    elsif ($first eq 'C')   { $cgibindir = $arg; }
    elsif ($first eq 'd')   { $updir = $arg; }
    elsif ($first eq 'D')   { $dir = $arg; }
    elsif ($first eq 'G')   { $cgifile = $arg; }
    elsif ($first eq 'h')   { $host = $arg; }
    elsif ($first eq 'i')   { $index = 1; }
    elsif ($first eq 's')   { $shortfiles = 1; }
    elsif ($first eq 'u')   { &usage(0); }
    else		    { &usage("$whatami: -$first is not an option.\n"); }
}

if (@ARGV == 0) {
    if ($isatty) {
        $infile = $outfile;		# Default input file if interactive
    } else {
	$infile = 'STDIN';		# Read STDIN if no args and not a tty
    }
} elsif (@ARGV == 1) {
    $infile = $ARGV[0];
} else {
    &usage("$whatami: Please specify one and only one file.\n");
}

$index = $index || $cgibin;		# $index is true if $cgibin is true

if ($cgibin && ! $host) {
    die "$whatami: Must specify host with -h if using -c.\n";
}

# Decide on HTML suffix and append it to filenames

$html = $shortfiles ? 'htm' : 'html';	# Max 3-character extension
$dir		.= ".$html";		# Directory in which to put the pieces
$headerfile	.= ".$html";		# HTML file for initial comments
$topfile	.= ".$html";		# Top-level HTML file (or moved notice)
$indexfile	.= ".$html";		# Symlink to $topfile
$listsfile	.= ".$html";		# Mailing list description HTML file

# Check for input file

unless ($infile eq 'STDIN') {
    die "$whatami: $infile doesn't exist!\n"	unless -e $infile;
    die "$whatami: $infile is unreadable!\n"	unless -r _;
    die "$whatami: $infile is empty!\n"		unless -s _;
}

# Check for output directory and create if necessary

if (-e $dir) {
    -d _ || die "$whatami: $dir is not a directory!\n";
    -r _ && -w _ && -x _ || die "$whatami: $dir is inaccessible!\n"
} else {
    mkdir($dir, 0755) || die "$whatami: Can't create $dir!\n";
}

# Slurp manpage

if ($infile eq 'STDIN') {
    @man = <STDIN>;
} else {
    open(MAN, $infile) || die "$whatami: Error opening $infile!\n";
    @man = <MAN>;
    close MAN;
}

# Print manpage to HTML directory (can't use cp if we're reading from STDIN)

open(MAN, ">$dir/$outfile") || die "$whatami: Can't open $dir/$outfile!\n";
print MAN @man;
close MAN;

# Copy script to HTML directory

(system("cp $0 $dir") >> 8) && die "$whatami: Can't copy $0 to $dir!\n";

# Link top.html to index.html in case someone looks at tcsh.html/

system("rm -f $dir/$indexfile");    # Some systems can't ln -sf
(system("ln -s $topfile $dir/$indexfile") >> 8)
    && die "$whatami: Can't link $topfile to $dir/$indexfile!\n";

### Get title and section headings

$comment = 0;			    # 0 for text, 1 for ignored text
@sectionlines = (0);		    # First line of section
@sectiontypes = (0);		    # H or S
@sectiontexts = ('Header');	    # Text of section heading
@sectionfiles = ($headerfile);	    # Filename in which to store section
%name = ();			    # Array of name anchors
@name = () if $index;		    # Ordered array of name anchors
$font = '';		    	    # '' to not make names, 'B' or 'I' to do so

$line = 0;
foreach (@man) {
    if (/^\.ig/) {		    # Start ignoring
	$comment = 1;
    } elsif (/^\.\./) {		    # Stop ignoring
	$comment = 0;
    } elsif (! $comment) {	    # Not in .ig'ed section; do stuff
	
	# nroff special characters
	
	s/\\-/-/g;		    # \-
	s/\\^//g;		    # \^
	s/^\\'/'/;		    # leading ' escape
	s/^\\(\s)/$1/;		    # leading space escape
	s/\\(e|\\)/\\/g;	    # \e, \\; must do this after other escapes

	# HTML special characters; deal with these before adding more
	
	s/&/&amp\;/g;
	s/>/&gt\;/g;
	s/</&lt\;/g;
	
	# Get title
	
	if (/^\.TH\s+(\w+)\s+(\w+)\s+\"([^\"]*)\"\s+\"([^\"]*)\"/) {
	    $title = "$1($2) $4 ($3) $1($2)";
	}
	
	# Build per-section info arrays
	
	if (($type, $text) = /^\.S([HS])\s+\"?([^\"]*)\"?/) {

	    push(@sectionlines, $line);	    # Index of first line of section
	    push(@sectiontypes, $type eq 'H' ? 0 : 1);	# Type of section
	    $text =~ s/\s*$//;		    # Remove trailing whitespace
	    push(@sectiontexts, $text);	    # Title of section (key for href)
	    $text =~ s/\s*\(\+\)$//;	    # Remove (+)
	    if ($shortfiles) {
		$file = $#sectionlines;	    # Short filenames; use number
	    } else {
		$file = $text;		    # Long filenames; use title
		$file =~ s/[\s\/]+/_/g;	    # Replace whitespace and / with _
	    }
	    $file .= ".$html" unless $single;
	    push(@sectionfiles, $file);	    # File in which to store section
	    $name{"$text B"} = ($single ? '#' : '') . $file;
					    # Index entry for &make_hrefs
	    push(@name, "$text\t" . $name{"$text B"}) if $index;
					    # Index entry for CGI script
	    # Look for anchors in the rest of this section if $link_me{$text}
	    # is non-null, and mark them with the font which is its value

	    $font = $link_me{$text};
    	}
	&make_name(*name, *font, *file, *index, *_) if $font;
    }
    $line++;
}

### Make top page

open(TOP, ">$dir/$topfile");
select TOP;

# Top page header

print <<EOP;
<HEAD>
<TITLE>$title</TITLE>
</HEAD>
<BODY>
<A NAME="top"></A>
<H1>$title</H1>
<HR>
EOP

# FORM block, if we're making an index

$action = $cgibin ? "http://$host/$cgibindir/$cgifile" : $cgifile;

print <<EOP if $index;
<FORM METHOD="GET" ACTION="$action">
Go directly to a section, command or variable: <INPUT NAME="input">
</FORM>
EOP

# Table of contents

print <<EOP;
<H2>
EOP

foreach $section (1 .. $#sectionlines) {
    if ($sectiontypes[$section - 1] < $sectiontypes[$section]) {
	print "</H2> <menu>\n";	    # Indent, smaller font
    } elsif ($sectiontypes[$section - 1] > $sectiontypes[$section]) {
	print "</menu> <H2>\n";	    # Outdent, larger font
    }
    if ($inline_me{$sectiontexts[$section]}) {    # Section is in %inline_me
	
	# Print section inline
	
	print "$sectiontexts[$section]\n";
	print "</H2> <menu>\n";	    # Indent, smaller font
	&printsectionbody(*man, *sectionlines, *section, *name);
	print "</menu> <H2>\n";	    # Outdent, larger font
    } else {
	
	# Print link to section
	
	print "<A HREF=\"", $single ? '#' : '',
	    "$sectionfiles[$section]\">$sectiontexts[$section]</A><BR>\n";
    }
}

print <<EOP;
</H2>
EOP

print "<HR>\n" if $single;

### Make sections

foreach $section (0 .. $#sectionlines) {

    # Skip inlined sections

    next if $inline_me{$sectiontexts[$section]};
    
    if ($single) {

	# Header
    
	print <<EOP if $section;	# Skip header section
<H2><A NAME="$sectionfiles[$section]">$sectiontexts[$section]</A></H2>
<menu>
EOP
	&printsectionbody(*man, *sectionlines, *section, *name);
	print <<EOP if $section;	# Skip header section
<A HREF="#top">Table of Contents</A>
</menu>
EOP

    } else {

	# Make pointer line for header and trailer
	
	$pointers  = "<A HREF=\"$topfile\">Up</A>";
	$pointers .= "\n<A HREF=\"$sectionfiles[$section + 1]\">Next</A>"
	    if ($section < $#sectionlines) &&
	    ! $inline_me{$sectiontexts[$section + 1]};
	$pointers .= "\n<A HREF=\"$sectionfiles[$section - 1]\">Previous</A>"
	    if ($section > 1) &&		# section 0 is initial comments
	    ! $inline_me{$sectiontexts[$section - 1]};
    
	# Header

	open(OUT, ">$dir/$sectionfiles[$section]");
	select OUT;
	print <<EOP;
<HEAD>
<TITLE>$sectiontexts[$section]</TITLE>
</HEAD>
<BODY>
$pointers
<H2>$sectiontexts[$section]</H2>
EOP
	&printsectionbody(*man, *sectionlines, *section, *name);

	# Trailer

	print <<EOP;
$pointers
</BODY>
EOP

    }
}

select TOP unless $single;

# Top page trailer

print <<EOP;
</H2>
<HR>
Here are the <A HREF="$outfile">nroff manpage</A> (175K)
from which this HTML version was generated,
the <A HREF="$script">Perl script</A> which did the conversion
and the <A HREF="ftp://ftp.astron.com/pub/tcsh/">
complete source code</A> for <I>tcsh</I>.
<HR>
<I>tcsh</I> is maintained by
Christos Zoulas <A HREF="mailto:christos\@gw.com">&lt;christos\@gw.com&gt;</A>
and the <A HREF="$listsfile"><I>tcsh</I> maintainers' mailing list</A>.
Dave Schweisguth <A HREF="mailto:dcs\@proton.chem.yale.edu">&lt;dcs\@proton.chem.yale.edu&gt;</A>
wrote the manpage and the HTML conversion script.
</BODY>
EOP

close TOP;

### Make lists page

open(LISTS, ">$dir/$listsfile");
select LISTS;
while(($_ = <DATA>) ne "END\n") {   # Text stored after __END__
    s/TOPFILEHERE/$topfile/;
    print;
}
close LISTS;

### Make search script

if ($index) {

    # URL of $dir; see comments in search script

    $root = $cgibin
	? "'http://$host/" . ($updir ? "$updir/" : '') . "$dir/'"
	: '"http://$ENV{\'SERVER_NAME\'}:$ENV{\'SERVER_PORT\'}" . (($_ = $ENV{\'SCRIPT_NAME\'}) =~ s|[^/]*$||, $_)';

    # String for passing @name to search script

    $name = join("',\n'", @name);

    open(TOP, ">$dir/$cgifile");
    select TOP;
    while(($_ = <DATA>) ne "END\n") {   # Text stored after __END__
	s/ROOTHERE/$root/;
	s/NAMEHERE/$name/;
	s/TOPFILEHERE/$topfile/;
	print;
    }
    close TOP;
    chmod(0755, "$dir/$cgifile") ||
	die "$whatami: Can't chmod 0755 $dir/$cgifile!\n";
    warn "$whatami: Don't forget to move $dir/$cgifile to /$cgibindir.\n"
	if $cgibin;
}

### That's all, folks

exit;

### Subroutines

# Process and print the body of a section

sub printsectionbody {

    local(*man, *sectionlines, *sline, *name) = @_;	# Number of section
    local($sfirst, $slast, @paralines, @paratypes, $comment, $dl, $pline,
	  $comment, $pfirst, $plast, @para, @tag, $changeindent);

    # Define section boundaries

    $sfirst = $sectionlines[$sline] + 1;
    if ($sline == $#sectionlines) {
	$slast = $#man;
    } else {
	$slast = $sectionlines[$sline + 1] - 1;
    }

    # Find paragraph markers, ignoring those between '.ig' and '..'

    if ($man[$sfirst] =~ /^\.[PIT]P/) {
	@paralines = ();
	@paratypes = ();
    } else {
	@paralines = ($sfirst - 1);		# .P follows .S[HS] by default
	@paratypes = ('P');
    }
    $comment = 0;
    foreach ($sfirst .. $slast) {
	if ($man[$_] =~ /^\.ig/) {		# Start ignoring
	    $comment = 1;
	} elsif ($man[$_] =~ /^\.\./) {		# Stop ignoring
	    $comment = 0;
	} elsif (! $comment && $man[$_] =~ /^\.([PIT])P/) {
	    push(@paralines, $_);
	    push(@paratypes, $1);
	}
    }

    # Process paragraphs

    $changeindent = 0;
    $dl = 0;
    foreach $pline (0 .. $#paralines) {

	@para = ();
	$comment = 0;

	# Define para boundaries

	$pfirst = $paralines[$pline] + 1;
	if ($pline == $#paralines) {
	    $plast = $slast;
	} else {
	    $plast = $paralines[$pline + 1] - 1;
	}

	foreach (@man[$pfirst .. $plast]) {
	    if (/^\.ig/) {		    # nroff begin ignore
		if ($comment == 0) {
		    $comment = 2;
		    push(@para, "<!--\n");
		} elsif ($comment == 1) {
		    $comment = 2;
		} elsif ($comment == 2) {
		    s/--/-/g;		    # Remove double-dashes in comments
		    push(@para, $_);
		}
	    } elsif (/^\.\./) {		    # nroff end ignore
		if ($comment == 0) {
		    ;
		} elsif ($comment == 1) {
		    ;
		} elsif ($comment == 2) {
		    $comment = 1;
		}
	    } elsif (/^\.\\\"/) {	    # nroff comment
		if ($comment == 0) {
		    $comment = 1;
		    push(@para, "<!--\n");
		    s/^\.\\\"//;
		} elsif ($comment == 1) {
		    s/^\.\\\"//;
		} elsif ($comment == 2) {
		    ;
		}
		s/--/-/g;		    # Remove double-dashes in comments
		push(@para, $_);
	    } else {			    # Nothing to do with comments
		if ($comment == 0) {
		    ;
    		} elsif ($comment == 1) {
		    $comment = 0;
		    push(@para, "-->\n");
		} elsif ($comment == 2) {
		    s/--/-/g;		    # Remove double-dashes in comments
		}

		unless ($comment) {
		
		    if (/^\.TH/) {	    # Title; got this already
			next;
		    } elsif (/^\.PD/) {	    # Para spacing; unimplemented
			next;
		    } elsif (/^\.RS/) {	    # Indent (one width only)
			$changeindent++;
			next;
		    } elsif (/^\.RE/) {	    # Outdent
			$changeindent--;
			next;
		    }

		    # Line break
		    s/^\.br.*/<BR>/;

		    # More nroff special characters

		    s/^\\&amp\;//;	    # leading dot escape; save until
					    #   now so leading dots aren't
					    #   confused with ends of .igs

		    &make_hrefs(*name, *_);			
		}
		push(@para, $_);
	    }
	}
	
	push(@para, "-->\n") if $comment;   # Close open comment
	
    	# Print paragraph

	if ($paratypes[$pline] eq 'P') {
	    &font(*para);
	    print   @para;
	} elsif ($paratypes[$pline] eq 'I') {
	    &font(*para);
	    print   "<menu>\n",
		    @para,
		    "</menu>\n";
	} else {			# T
	    @tag = shift(@para);
	    &font(*tag);
	    &font(*para);
	    print   "<DL compact>\n" unless $dl;
	    print   "<DT>\n",
		    @tag,
		    "<DD>\n",
		    @para;
	    if ($pline == $#paratypes || $paratypes[$pline + 1] ne 'T') {
		# Perl 5 lossage alert
		# Next para is not a definition list
		$dl = 0;		    # Close open definition list
		print "</DL>\n";
	    } else {
		$dl = 1;		    # Leave definition list open
	    }
	}
	print "<P>\n";
	
	# Indent/outdent the *next* para
	
	while ($changeindent > 0) {
	    print "<menu>\n";
	    $changeindent--;
	}
	while ($changeindent < 0) {
	    print "</menu>\n";
	    $changeindent++;
	}
    }
    1;
}

# Make one name anchor in a line; cue on fonts (.B or .I) but leave them alone

sub make_name {

    local(*name, *font, *file, *index, *line) = @_;
    local($text);

    if (($text) = ($line =~ /^\.[BI]\s+([^\s\\]+)/)) {	# Found pattern

	if (
	    $text !~ /^-/		    # Avoid lists of options
	    && (length($text) > 1	    # and history escapes
		||  $text =~ /^[%:@]$/)	    # Special pleading for %, :, @
	    && ! $name{"$text $font"}	    # Skip if there's one already
	) {
	    # Record link
	    
	    $name{"$text $font"} = ($single ? '' : $file) . "#$text";
	    push(@name, "$text\t" . $name{"$text $font"}) if $index;
	    
	    # Put in the name anchor
    
	    $line =~ s/^(\.[BI]\s+)([^\s\\]+)/$1<A NAME=\"$text\">$2<\/A>/;
	}
    }
    $line;
}

# Make all the href anchors in a line; cue on fonts (\fB ... \fR or
# \fI ... \fR) but leave them alone

sub make_hrefs {

    local(*name, *line) = @_;
    local(@pieces, $piece);

    @pieces = split(/(\\f[BI][^\\]*\\fR)/, $line);
    
    $piece = 0;
    foreach (@pieces) {
	if (/\\f([BI])([^\\]*)\\fR/	# Found a possibility

	# It's not followed by (, i.e. it's not a manpage reference

	&& substr($pieces[$piece + 1], 0, 1) ne '(') {
	    $key = "$2 $1";
	    if ($name{$key}) {			# If there's a matching name
		s/(\\f[BI])([^\\]*)(\\fR)/$1<A HREF=\"$name{$key}\">$2<\/A>$3/;
	    }
	}
	$piece++;
    }
    $line = join('', @pieces);
}

# Convert nroff font escapes to HTML
# Expects comments and breaks to be in HTML form already

sub font {

    local(*para) = @_;
    local($i, $j, @begin, @end, $part, @pieces, $bold, $italic);

    return 0 if $#para == -1;   # Ignore empty paragraphs
				# Perl 5 lossage alert

    # Find beginning and end of each part between HTML comments

    $i = 0;
    @begin = ();
    @end = ();
    foreach (@para) {
	push(@begin, $i + 1) if /^-->/ || /^<BR>/;
	push(@end, $i - 1) if /^<!--/ || /^<BR>/;
	$i++;
    }
    if ($para[0] =~ /^<!--/ || $para[0] =~ /^<BR>/) {
	shift(@end);
    } else {
	unshift(@begin, 0);	# Begin at the beginning
    }
    if ($para[$#para] =~ /^-->/ || $para[$#para] =~ /^<BR>/) {
	pop(@begin);
    } else {
	push(@end, $#para);	# End at the end
    }

    # Fontify each part

    $bold = $italic = 0;
    foreach $i (0 .. $#begin) {
	$* = 1;
	$part = join('', @para[$begin[$i] .. $end[$i]]);
	$part =~ s/^\.([BI])\s+(.*)$/\\f$1$2\\fR/g;	    # .B, .I
	@pieces = split(/(\\f[BIR])/, $part);
	$part = '';
	foreach $j (@pieces) {
	    if ($j eq '\fB') {
		if ($italic) {
		    $italic = 0;
		    $part .= '</I>';
		}
		unless ($bold) {
		    $bold = 1;
		    $part .= '<B>';
		}
	    } elsif ($j eq '\fI') {
		if ($bold) {
		    $bold = 0;
		    $part .= '</B>';
		}
		unless ($italic) {
		    $italic = 1;
		    $part .= '<I>';
		}
	    } elsif ($j eq '\fR') {
		if ($bold) {
		    $bold = 0;
		    $part .= '</B>';
		} elsif ($italic) {
		    $italic = 0;
		    $part .= '</I>';
		}
	    } else {
		$part .= $j;	
	    }
	}
	$* = 0;

	# Close bold/italic before break

	if ($end[$i] == $#para || $para[$end[$i] + 1] =~ /^<BR>/) {
	    # Perl 5 lossage alert
	    if ($bold) {
		$bold = 0;
		$part =~ s/(\n)?$/<\/B>$1\n/;
	    } elsif ($italic) {
		$italic = 0;
		$part =~ s/(\n)?$/<\/I>$1\n/;
	    }
	}

	# Rebuild this section of @para

	foreach $j ($begin[$i] .. $end[$i]) {
	    $part =~ s/^([^\n]*(\n|$))//;
	    $para[$j] = $1;
	}
    }

    # Close bold/italic on last non-comment line
    # Do this only here because fonts pass through comments

    $para[$end[$#end]] =~ s/(\n)?$/<\/B>$1/ if $bold;
    $para[$end[$#end]] =~ s/(\n)?$/<\/I>$1/ if $italic;
}

sub usage {
    local ($message) = $_[0];

    warn $message if $message;
    warn <<EOP;
Usage: $whatami [-1icsu] [-C dir] [-d dir] [-h host] [file]
Without [file], reads from tcsh.man or stdin.
-1	    Makes a single page instead of a table of contents and sections
-i	    Makes a CGI searchable index script, tcsh.html/tcsh.cgi, intended
	    for a server which respects the .cgi extension in any directory.
-c	    Like -i,  but the CGI script is intended for a server which wants
	    scripts in /cgi-bin (or some other privileged directory separate
	    from the rest of the HTML) and must be moved there by hand.
-C dir	    Uses /dir instead of /cgi-bin as the CGI bin dir.
	    Meaningless without -c.
-d dir	    Uses /dir/tcsh.html instead of /tcsh.html as the HTML dir.
	    Meaningless without -c.
-D dir	    Uses /dir.html instead of /tcsh.html as the HTML dir.
	    Meaningless without -c.
-G name	    Uses name instead of tcsh.cgi as the name of the CGI script.
	    Meaningless without -c or -i.
-h host	    Uses host as the host:port part of the URL to the entry point.
	    Meaningless without -c.
-s	    Filenames are shorter (max 8 + 3) but less descriptive.
-u	    This message
EOP
    exit !! $message;
}

### Inlined documents. Watch for *HERE tokens.

__END__
<HEAD>
<TITLE>The tcsh mailing lists</TITLE>
</HEAD>
<BODY>
<A HREF="TOPFILEHERE">Up</A>
<H2>The <I>tcsh</I> mailing lists</H2>
There are three <I>tcsh</I> mailing lists:
<DL>
<DT>
<I>tcsh@mx.gw.com</I>
<DD>
The <I>tcsh</I> maintainers and testers' mailing list.
<DT>
<I>tcsh-diffs@mx.gw.com</I>
<DD>
The same as <I>tcsh@mx.gw.com</I>, plus diffs for each new
patchlevel of <I>tcsh</I>.
<DT>
<I>tcsh-bugs@mx.gw.com</I>
<DD>
Bug reports.
</DL>
You can subscribe to any of these lists by sending mail to
<I><A HREF="mailto:listserv@mx.gw.com">listserv@mx.gw.com</A></I> with the
text "subscribe &lt;list name&gt; &lt;your name&gt;" on a line by
itself in the body. &lt;list name&gt; is the name of the mailing list,
without "@mx.gw.com", and &lt;your name&gt; is your real name, not your
email address. You can also ask the list server for help by sending
only the word "help".
<P>
<A HREF="TOPFILEHERE">Up</A>
</BODY>
END
#!/bin/sh

# Emulate #!/usr/local/bin/perl on systems without #!

eval '(exit $?0)' && eval 'exec perl -S $0 ${1+"$@"}'
& eval 'exec perl -S $0 $argv:q' if 0;

# Setup

# Location: doesn't work with relative URLs, so we need to know where to find
#   the top and section files.
# If the search engine is in /cgi-bin, we need a hard-coded URL.
# If the search engine is in the same directory, we can figure it out from CGI
#   environment variables.

$root = ROOTHERE;
$topfile = 'TOPFILEHERE';
@name = (
'NAMEHERE'
);

# Do the search

$input = $ENV{'QUERY_STRING'};
$input =~ s/^input=//;
$input =~ s/\+/ /g;
print "Status: 302 Found\n";
if ($input ne '' && ($key = (grep(/^$input/,  @name))[0] ||
			    (grep(/^$input/i, @name))[0] ||
			    (grep( /$input/i, @name))[0]   )) {
    $key =~ /\t([^\t]*)$/;
    print "Location: $root$1\n\n";
} else {
    print "Location: $root$topfile\n\n";
}
END