This problem has been bugging me and the solution is probably very simple.
But I "Can't see the wood for the trees"

I need to catch all output of the expect.pm
Specifically :
. $exp->exp_internal(1);
. $exp->debug(1);
and send it to a file
without it printing to the screen.

Changing from expect is not an option, as it is perfect
to run and capture an unreliable program.

# Define variables used to run the unreliable program
my ($par1, $par2, $par3) = @_;

    # Setup array to hold parameters to pass to runrep
    my @parameterss;
    # Add login parameters
    push (@parameters, $login);

    # Create the path name for the expect log file
    my $expect_log = "/tmp/output.tmp";

    # Open the expect log file
    open (EXPECT, ">$expect_log")
        or die ("Cannot open the expect log file: $expect_log $!\n");

    # Spawn program using perl expect module
    my $exp = Expect->spawn($program, @parameters)
        or die "Cannot spawn $program $login: $!\n";

    # Prevent the program's output from being shown on the screen as S
+TDOUT
    $exp->log_stdout(0);    # But I want to catch this into the $expec
+t_log file

    # Populate the expect log file with any output from the expect run
+rep
    $exp->log_file("$expect_log"); # This isn't catching the debug/exp
+_internal output

    $exp->exp_internal(1);
    $exp->debug(1);

    # Wait for program to initialise for 5 minutes only
    $exp->expect(300,[ qr/starting/]);

    # Read in the parameters
    $exp->send("read $parameters\n");

    # Send appropriate command to program
    $exp->send("run $program with parameters");

    # Wait for program to run or generate an error
    $exp->expect(18000,  [ qr/Error/i, sub { my $self = shift;
                                        $self->send("quit\n");exp_cont
+inue;}],
                        [ qr/success/i, sub { my $self = shift;
                                        $self->send("quit\n"); exp_con
+tinue;}]);

    my $output = $exp->exp_error();

    # Clear any output and close the program gently
    $exp->clear_accum();
    $exp->soft_close();

    # Close the except file
    close(EXPECT);


<\code>


This is a simple example of expect if anyone needs to run it

<readmore>
<code>

######################################################
#!/usr/bin/perl
#
# Fri Dec 13 23:10:54 PST 2002
#
# Copyright Tom Anderson 2002, All rights reserved.
# This program may be copied under the same terms as Perl itself.
# Please send modifications to t@tomacorp.com
#
#
# unreliable.pl - Simulate a program that sometimes just hangs 
#

my $VERSION=".01";

use strict;
use warnings;
use diagnostics;

if (rand(10) > 8)
{
  sleep 1 while 1 > 0;
}
else
{
  print "--------------------------------\n",
        "It worked this time, no problems\n",
        "--------------------------------\n";
}



##############################################

use warnings;
use diagnostics;
use Expect;

my $timeout=5;

foreach my $i (1..20)
{
  my $spawn_ok="not OK";

  my $exp = Expect->spawn("./unreliable.pl")
    or die "Cannot spawn unreliable process $!\n";

  $exp->expect($timeout,
    [
      'It worked',
        sub 
        {
          $spawn_ok = "OK";
          exp_continue;
        }
    ],
    [
      timeout =>
        sub 
        {
          print "Process timed out.\n";
        }
    ]
  );
  print "Status: $spawn_ok\n";
}
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