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version of this module may delay redirecting STDERR until one of the
CGI::Carp methods is called to prevent the performance hit.

=head1 MAKING PERL ERRORS APPEAR IN THE BROWSER WINDOW

If you want to send fatal (die, confess) errors to the browser, import
the special "fatalsToBrowser" subroutine:

    use CGI::Carp qw(fatalsToBrowser);
    die "Bad error here";

Fatal errors will now be echoed to the browser as well as to the log.
CGI::Carp arranges to send a minimal HTTP header to the browser so
that even errors that occur in the early compile phase will be seen.
Nonfatal errors will still be directed to the log file only (unless
redirected with carpout).

Note that fatalsToBrowser may B<not> work well with mod_perl version 2.0
and higher.

=head2 Changing the default message

By default, the software error message is followed by a note to
contact the Webmaster by e-mail with the time and date of the error.
If this message is not to your liking, you can change it using the
set_message() routine.  This is not imported by default; you should
import it on the use() line:

    use CGI::Carp qw(fatalsToBrowser set_message);
    set_message("It's not a bug, it's a feature!");

You may also pass in a code reference in order to create a custom
error message.  At run time, your code will be called with the text
of the error message that caused the script to die.  Example:

    use CGI::Carp qw(fatalsToBrowser set_message);
    BEGIN {
       sub handle_errors {
          my $msg = shift;
          print "<h1>Oh gosh</h1>";
          print "<p>Got an error: $msg</p>";
      }
      set_message(\&handle_errors);
    }

In order to correctly intercept compile-time errors, you should call
set_message() from within a BEGIN{} block.

=head1 DOING MORE THAN PRINTING A MESSAGE IN THE EVENT OF PERL ERRORS

If fatalsToBrowser in conjunction with set_message does not provide 
you with all of the functionality you need, you can go one step 
further by specifying a function to be executed any time a script
calls "die", has a syntax error, or dies unexpectedly at runtime
with a line like "undef->explode();". 

    use CGI::Carp qw(set_die_handler);
    BEGIN {
       sub handle_errors {
          my $msg = shift;
          print "content-type: text/html\n\n";
          print "<h1>Oh gosh</h1>";
          print "<p>Got an error: $msg</p>";

          #proceed to send an email to a system administrator,
          #write a detailed message to the browser and/or a log,
          #etc....
      }
      set_die_handler(\&handle_errors);
    }

Notice that if you use set_die_handler(), you must handle sending
HTML headers to the browser yourself if you are printing a message.

If you use set_die_handler(), you will most likely interfere with 
the behavior of fatalsToBrowser, so you must use this or that, not 
both. 

Using set_die_handler() sets SIG{__DIE__} (as does fatalsToBrowser),
and there is only one SIG{__DIE__}. This means that if you are 
attempting to set SIG{__DIE__} yourself, you may interfere with 
this module's functionality, or this module may interfere with 
your module's functionality.

=head1 SUPPRESSING PERL ERRORS APPEARING IN THE BROWSER WINDOW

A problem sometimes encountered when using fatalsToBrowser is
when a C<die()> is done inside an C<eval> body or expression.
Even though the
fatalsToBrower support takes precautions to avoid this,
you still may get the error message printed to STDOUT.
This may have some undesirable effects when the purpose of doing the
eval is to determine which of several algorithms is to be used.

By setting C<$CGI::Carp::TO_BROWSER> to 0 you can suppress printing
the C<die> messages but without all of the complexity of using
C<set_die_handler>.  You can localize this effect to inside C<eval>
bodies if this is desirable: For example:

 eval {
   local $CGI::Carp::TO_BROWSER = 0;
   die "Fatal error messages not sent browser"
 }
 # $@ will contain error message


=head1 MAKING WARNINGS APPEAR AS HTML COMMENTS

It is also possible to make non-fatal errors appear as HTML comments
embedded in the output of your program.  To enable this feature,
export the new "warningsToBrowser" subroutine.  Since sending warnings
to the browser before the HTTP headers have been sent would cause an
error, any warnings are stored in an internal buffer until you call
the warningsToBrowser() subroutine with a true argument:

    use CGI::Carp qw(fatalsToBrowser warningsToBrowser);
    use CGI qw(:standard);
    print header();
    warningsToBrowser(1);

You may also give a false argument to warningsToBrowser() to prevent