Source code for allhelp.pl

```
#!/usr/bin/perl
```
```
 
```
```
# allhelp.pl for Linux
```

# Display help for the Bourne Shell's internal commands and reserved words

```
# Written by Rob van der Woude
```
```
# http://www.robvanderwoude.com
```
```
 
```
```
use strict;
```
```
use warnings;
```
```
use Config;
```
```
use CGI qw(escapeHTML);
```
```
 
```
```
my $scriptver = '1.02';
```
```
 
```
```
# Abort if not running on Linux
```

if ( lc( $Config{osname} ) ne 'linux' ) {

	print "This script will run on Linux systems only.";

```
	exit 1;
```
```
}
```
```
 
```
```
my @cmds;
```
```
my @builtins;
```
```
my @coreutils;
```
```
my @reserved;
```
```
my %helplong;
```
```
my %helpshort;
```
```
my $outfile = 'allhelp_bash.html';
```
```
 
```

# Create a list of all internal commands for which help is available

open( SHELL, "-|", "bash", "-c", "compgen -b" );

```
while( <SHELL> ) {
```
```
	chomp;
```
```
	push( @builtins, $_ );
```
```
}
```
```
close( SHELL );
```
```
 
```

# Create a list of all reserved words for which help is available

open( SHELL, "-|", "bash", "-c", "compgen -k" );

```
while( <SHELL> ) {
```
```
	chomp;
```
```
	push( @reserved, $_ );
```
```
}
```
```
close( SHELL );
```
```
 
```
```
# Create a list of coreutils
```

open( SHELL, '-|', 'bash', '-c', 'info | grep -F "(coreutils)"');

```
while ( <SHELL> ) {
```
```
	chomp;
```

	if ( $_ =~ m/^\*\s+([a-z][a-z0-9]+):\s+\(coreutils\)\1/ ) {

		$_ =~ /^\*\s+([a-z][a-z0-9]+):\s+\(coreutils\)\1\s[^.]+\.\s+(.+)$/;

```
		push( @coreutils, $1 );
```
```
		my $anchor = &Anchor( $1 );
```
```
		$helpshort{ $anchor } = $2;
```
```
	}
```
```
}
```
```
close( SHELL );
```
```
 
```
```
 
```
```
# Merge the lists of commands
```
```
push( @cmds, @builtins );
```
```
push( @cmds, @reserved );
```
```
push( @cmds, @coreutils );
```
```
 
```

# Sort the list of commands, punction and numbers first

```
@cmds = sort {
```

	if ( $a =~ m/^[a-z]/i and $b !~ m/^[a-z]/i ) {

```
		return 1;
```

	} elsif ( $a !~ m/^[a-z]/i and $b =~ m/^[a-z]/i ) {

```
		return -1;
```
```
	} else {
```
```
		return $a cmp $b;
```
```
	}
```
```
} @cmds;
```
```
 
```

# Calculate available column width for 3 columns display with 3 characters spacing

```
my $cols = `tput cols`;
```
```
my $rows = `tput lines`;
```

my $colwidth = int( ( $cols - 6 ) / 3 );

```
 
```
```
# First display the Linux version
```
```
print &LinuxVer( ) . "\n\n";
```
```
 
```

# Display the list of commands in 3 columns

for ( my $i = 0; $i < @cmds; $i += 3 ) {

	printf '%-' . $colwidth . 's', $cmds[$i];

	if ( $i + 1 < @cmds ) { printf '   %-' . $colwidth . 's', $cmds[$i+1]; }

	if ( $i + 2 < @cmds ) { printf '   %-' . $colwidth . 's', $cmds[$i+2]; }

```
	print "\n";
```
```
}
```
```
 
```

# Display help for each command in the array

```
foreach my $cmd ( @cmds ) {
```
```
	print "\nHelp for '$cmd'\n\n";
```
```
	my $anchor = &Anchor( $cmd );
```
```
	my $helptext = '';
```

	if ( grep { $_ eq $cmd } @coreutils ) {

```
		# Use info command for coreutils
```

		open( SHELL, "-|", "bash", "-c", "info $cmd | grep -F \"\"" );

		# Read resulting help text from STDOUT

```
		while ( <SHELL> ) {
```
```
			$helptext .= $_;
```
```
		}
```
```
		close( SHELL );
```
```
		if ( $helptext ) {
```
```
			$helptext =~ s/\342\200\230/'/g;
```
```
			$helptext =~ s/\342\200\231/'/g;
```

			$helptext =~ s/^\/([^\n]*\n){3}\d+\.\d+\s+//;

```
			$helptext =~ s/\n=+\n/\n/g;
```
```
			$helplong{ $anchor } = $helptext;
```
```
		}
```
```
	} else {
```

		# Use help command for reserved words and builtin commands

		# Escape the commands, otherwise bash may break on parenthesis

```
		my $esccmd = quotemeta( $cmd );
```

		# Run help command with escaped command name

		open( SHELL, "-|", "bash", "-c", "help $esccmd 2> /dev/null" );

		# Read resulting help text from STDOUT

```
		while ( <SHELL> ) {
```
```
			$helptext .= $_;
```
```
		}
```
```
		close( SHELL );
```
```
		if ( "$helptext" !~ m/^\s*$/g ) {
```
```
			$helplong{ $anchor } = $helptext;
```
```
			# Display help text
```
```
			print escapeHTML( $helptext );
```
```
			# Get short help text summary
```

			my $firstline = $cmd . ': ' . $cmd . '[^\n]*\n\s+';

```
			if ( $cmd ne $esccmd ) {
```

				$firstline = $esccmd . '[^a-z:\n]*: ' . $esccmd . '[^\n]*\n\s+';

```
			}
```

			"$helptext" =~ /$firstline((.|\n)*?)\n\s*\n/;

```
			$helpshort{ $anchor } = $1;
```
```
		}
```
```
	}
```
```
}
```
```
 
```
```
print "\n\n";
```
```
 
```

# Remove commands from list if no help is available

# Use reverse order to prevent skipping 1 each time an element is removed from the array

for ( my $i = @cmds - 1; $i >= 0; $i-- ) {

```
	my $cmd = $cmds[$i];
```
```
	my $anchor = &Anchor( $cmd );
```

	unless ( exists( $helplong{ $anchor } ) ) {

```
		my $index = 0;
```

		$index++ until $cmds[$index] eq $cmd or $index == @cmds;

```
		splice( @cmds, $index, 1 );
```
```
	}
```
```
}
```
```
 
```
```
# Write the help to a HTML file
```
```
my $htmlhelp = &HTMLHead( );
```
```
$htmlhelp .= &HTMLList( );
```
```
foreach my $cmd ( @cmds ) {
```
```
	$htmlhelp .= &HTMLCommand( $cmd );
```
```
}
```
```
$htmlhelp .= &HTMLFoot( );
```

open( HTML, ">", $outfile ) or die( "Error writing HTML to file \"$outfile\"." );

```
print HTML $htmlhelp;
```
```
close( HTML );
```
```
 
```

# Open the newly created HTML file in the default browser (may generate warning messages with Firefox)

```
if ( `which sensible-browser` ) {
```
```
	exec( 'sensible-browser', $outfile );
```

} elsif ( `which xdg-open > /dev/null` ) {

```
	exec( 'xdg-open', $outfile );
```

} elsif ( `which gnome-open > /dev/null` ) {

```
	exec( 'gnome-open', $outfile );
```
```
} elsif ( `which x-www-browser` ) {
```
```
	exec( 'x-www-browser', $outfile );
```
```
} else {
```

	my $browser = `gconftool -g /desktop/gnome/url-handlers/http/command 2> /dev/null`;

```
	if ( $browser ) {
```
```
		exec( $browser, $outfile );
```
```
	} else {
```

		die "Unable to locate default browser; open \"$outfile\" manually.";

```
	}
```
```
}
```
```
 
```
```
 
```
```
 
```
```
 
```
```
sub Alphabet( ) {
```

	my $html = "<table class=\"Alphabet\">\n<tr>\n";

```
	my $found = 0;
```
```
	foreach my $c ( @cmds ) {
```
```
		my $A = uc( substr( $c, 0, 1 ) );
```
```
		if ( $A !~ /[A-Z]/ ) {
```
```
			$found = 1;
```
```
		}
```
```
	}
```
```
	if ( $found ) {
```

		$html .= "\t<th><a href=\"#Punc\">#</a></th>\n";

```
	} else {
```

		$html .= "\t<th style=\"color: gray;\">#</th>\n";

```
	}
```
```
	foreach my $a ( 'a' .. 'z' ) {
```
```
		my $A = uc( $a );
```
```
		my $found = 0;
```
```
		foreach my $c ( @cmds ) {
```

			if ( lc( substr( $c, 0, 1 ) ) eq $a ) {

```
				$found = 1;
```
```
			}
```
```
		}
```
```
		if ( $found ) {
```

			$html .= "\t<th><a href=\"#$A\">$A</a></th>\n";

```
		} else {
```

			$html .= "\t<th style=\"color: gray;\">$A</th>\n";

```
		}
```
```
	}
```
```
	$html .= "</tr>\n</table>\n";
```
```
	return $html;
```
```
}
```
```
 
```
```
 
```
```
sub Anchor( ) {
```
```
	my $cmd = $_[0];
```
```
	my $firstchar = substr( $cmd, 0, 1 );
```
```
	my $anchor = $cmd;
```

	if ( $firstchar eq "." ) { $anchor = "dot"; }

	if ( $firstchar eq ":" ) { $anchor = "colon"; }

	if ( $firstchar eq '!' ) { $anchor = "exclamation"; }

	if ( $firstchar eq "(" ) { $anchor = "parentheses"; }

	if ( $firstchar eq "[" ) { $anchor = "brackets"; }

	if ( $firstchar eq "{" ) { $anchor = "braces"; }

```
	return $anchor;
```
```
}
```
```
 
```
```
 
```
```
sub HTMLCommand( ) {
```
```
	my $cmd = $_[0];
```
```
	my $anchor = &Anchor( $cmd );
```
```
	my $type;
```
```
	my $class;
```

	if ( grep { $_ eq $cmd } @coreutils ) {

```
		$class = 'CoreUtils';
```

		$type = "<p><strong>coreutils</strong></p>\n\n";

	} elsif ( grep { $_ eq $cmd } @builtins ) {

```
		$class = 'BuiltIn';
```

		$type = "<p><strong>builtin command</strong></p>\n\n";

	} elsif ( grep { $_ eq $cmd } @reserved ) {

```
		$class = 'ReservedWord';
```

		$type = "<p><strong>reserved word</strong></p>\n\n";

```
	} else {
```
```
		$class = '';
```
```
		$type = '';
```
```
	}
```
```
	my $html = '';
```
```
	if ( $class ne '' ) {
```

		$html .= "<div class=\"$class\">\n\n";

```
	}
```

	$html .= "<h2 id=\"$anchor\">$cmd</h2>\n\n$type<pre>";

	$html .= escapeHTML( $helplong{ $anchor } );

	$html .= "</pre>\n\n<div class=\"Center\"><a href=\"#\">Back to the top of this page</a></div>\n\n<p>&nbsp;</p>\n\n";

```
	if ( $class ne '' ) {
```
```
		$html .= "</div>\n\n";
```
```
	}
```
```
	return $html;
```
```
}
```
```
 
```
```
 
```
```
sub HTMLFoot( ) {
```
```
	my @now = localtime( );
```

	my $html = "<table>\n<tr id=\"Note\">\n\t<td class=\"Bold Top\">Note:</td>\n\t<td>&nbsp;</td>\n";

	$html .= "\t<td>Not all reserved words are listed here, only the ones for which help is available.</td>\n</tr>\n</table>\n\n";

	$html .= "<p>&nbsp;</p>\n\n<div class=\"Center\">\n\n<p>This HTML help was generated on ";

	$html .= sprintf( "%4d-%02d-%02d", $now[5] + 1900, $now[4], $now[3] );

	$html .= " by <a href=\"http://www.robvanderwoude.com/perlexamples.php#allhelp\">";

	$html .= "allhelp.pl</a>, Version $scriptver<br />\n";

	$html .= "Written by Rob van der Woude<br />\n";

	$html .= "<a href=\"http://www.robvanderwoude.com/\">http://www.robvanderwoude.com</a></p>\n\n";

	$html .= "</div>\n\n</div>\n\n</div>\n\n<p>&nbsp;</p>\n\n</body>\n</html>";

```
}
```
```
 
```
```
 
```
```
sub HTMLHead( ) {
```
```
	my $title = &LinuxVer( );
```
```
	my $html = <<"END_OF_HTML";
```

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">

```
<html lang="en">
```
```
<head>
```

<meta http-equiv="X-UA-Compatible" content="IE=EmulateIE7;FF=3;OtherUA=4">

<meta name="robots" content="index,follow">

<meta name="generator" content="allhelp.pl, Version $scriptver, by Rob van der Woude, www.robvanderwoude.com">

<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">

<meta http-equiv="Content-Style-Type" content="text/css">

```
 
```
```
<title>Help for $title</title>
```
```
 
```
```
<style type="text/css">
```
```
a, a.visited
```
```
{
```
```
	color: blue;
```
```
}
```
```
 
```
```
td.Command
```
```
{
```
```
	vertical-align: top;
```
```
	padding-left: 10px;
```
```
	padding-right: 5px;
```
```
	font-weight: bold;
```
```
	white-space: nowrap;
```
```
}
```
```
 
```
```
th
```
```
{
```
```
	vertical-align: top;
```
```
}
```
```
 
```
```
table.Alphabet
```
```
{
```
```
	border: 2px solid blue;
```
```
	margin: 0 auto 0 auto;
```
```
	text-align: center;
```
```
	vertical-align: middle;
```
```
	width: 100%;
```
```
}
```
```
 
```
```
table.Alphabet th
```
```
{
```
```
	padding: 5px;
```
```
	width: 4%;
```
```
}
```
```
 
```
```
table.List
```
```
{
```
```
	margin: 0 auto 0 auto;
```
```
	width: 100%;
```
```
}
```
```
 
```
```
table.List th
```
```
{
```
```
	background-color: blue;
```
```
	color: white;
```
```
	font-size: 120%;
```
```
	font-weight: bold;
```
```
	padding-left: 10px;
```
```
}
```
```
 
```
```
pre
```
```
{
```
```
	white-space: pre-wrap;
```
```
}
```
```
 
```
```
.Bold
```
```
{
```
```
	font-weight: bold;
```
```
}
```
```
 
```
```
.Center
```
```
{
```
```
	text-align: center;
```
```
	margin-left: auto;
```
```
	margin-right: auto;
```
```
}
```
```
 
```
```
.Left
```
```
{
```
```
	text-align: left;
```
```
}
```
```
 
```
```
.Smallfont
```
```
{
```
```
	font-size: 60%;
```
```
}
```
```
 
```
```
.Top
```
```
{
```
```
	vertical-align: top;
```
```
}
```
```
</style>
```
```
 
```
```
</head>
```
```
<body>
```
```
 
```
```
<h2 class="Center">Help for</h2>
```
```
 
```

<h1 class="Center">CoreUtils, internal Bash commands</h1>

```
 
```

<h2 class="Center">and reserved words&nbsp;<sup>(<a href="#Note">*</a>)</sup></h2>

```
 
```
```
<h3 class="Center">$title</h3>
```
```
 
```
```
<p>&nbsp;</p>
```
```
 
```

<div class="Center" style="width: 50em;">

```
 
```
```
<div class="Left" style="width: 50em;">
```
```
 
```
```
END_OF_HTML
```
```
 
```
```
	$html .= Alphabet( );
```
```
	return $html;
```
```
}
```
```
 
```
```
 
```
```
sub HTMLList( ) {
```
```
	my $lastfirstchar = '';
```
```
	my $html = "<table class=\"List\">\n";
```

	$html .= "<tr id=\"Punc\">\n\t<th colspan=\"2\">Punctuation</th>\n</tr>\n";

	$html .= "<tr>\n\t<td colspan=\"2\">&nbsp;</td>\n</tr>\n";

```
	foreach my $cmd ( @cmds ) {
```
```
		my $firstchar = '';
```
```
		if ( "$cmd" =~ m/^[a-z]/ ) {
```
```
			"$cmd" =~ /^([a-z])/;
```
```
			$firstchar = uc( $1 );
```
```
			if ( $firstchar ) {
```

				if ( $firstchar ne $lastfirstchar ) {

					$html .= "<tr>\n\t<td colspan=\"2\">&nbsp;</td>\n</tr>\n";

					$html .= "<tr id=\"$firstchar\">\n\t<th colspan=\"2\">$firstchar</th>\n</tr>\n";

					$html .= "<tr>\n\t<td colspan=\"2\">&nbsp;</td>\n</tr>\n";

```
				}
```
```
			}
```
```
		}
```
```
		$lastfirstchar = $firstchar;
```
```
		my $anchor = &Anchor( $cmd );
```

		my $help = escapeHTML( $helpshort{ $anchor } );

```
		my $class;
```

		if ( grep { $_ eq $cmd } @coreutils ) {

```
			$class = ' class="CoreUtils"';
```

		} elsif ( grep { $_ eq $anchor } @builtins ) {

```
			$class = ' class="BuiltIn"';
```

		} elsif ( grep { $_ eq $anchor } @reserved ) {

```
			$class = ' class="ReservedWord"';
```
```
		} else {
```
```
			$class = '';
```
```
		}
```
```
		$help =~ s/[\t ]+/ /g;
```

		$html .= "<tr$class>\n\t<td class=\"Command\"><a href=\"#$anchor\">$cmd</a></td>\n\t<td>$help</td>\n</tr>\n";

```
	}
```

	$html .= "</table>\n\n<p>&nbsp;</p>\n\n";

```
	return $html;
```
```
}
```
```
 
```
```
 
```
```
sub LinuxVer( ) {
```
```
	my $os = '';
```

	open( SHELL, "-|", "bash", "-c", "uname -sirv" );

```
	while( <SHELL> ) {
```
```
		chomp( $os = $_ );
```
```
	}
```
```
	close( SHELL );
```
```
	if ( $os eq '' ) {
```

		$os = "$Config{osname} $Config{osvers}";

```
	}
```
```
	return $os;
```
```
}
```
```
 
```