diff --git a/bin/pt-query-digest b/bin/pt-query-digest
index 896b1f95..3b693bcf 100755
--- a/bin/pt-query-digest
+++ b/bin/pt-query-digest
@@ -81,6 +81,7 @@ our $VERSION = '2.2.1';
 # ###########################################################################
 {
 package Lmo::Utils;
+
 use strict;
 use warnings qw( FATAL all );
 require Exporter;
@@ -88,7 +89,12 @@ our (@ISA, @EXPORT, @EXPORT_OK);
 
 BEGIN {
    @ISA = qw(Exporter);
-   @EXPORT = @EXPORT_OK = qw(_install_coderef _unimport_coderefs _glob_for _stash_for);
+   @EXPORT = @EXPORT_OK = qw(
+      _install_coderef
+      _unimport_coderefs
+      _glob_for
+      _stash_for
+   );
 }
 
 {
@@ -272,7 +278,6 @@ sub meta {
    return Lmo::Meta->new(class => $class);
 }
 
-
 1;
 }
 # ###########################################################################
@@ -3789,6 +3794,7 @@ sub new {
       sessions       => {},
       o              => $args{o},
       fake_thread_id => 2**32,   # see _make_event()
+      null_event     => $args{null_event},
    };
    PTDEBUG && $self->{server} && _d('Watching only server', $self->{server});
    return bless $self, $class;
@@ -3809,7 +3815,7 @@ sub parse_event {
       $server .= ":$self->{port}";
       if ( $src_host ne $server && $dst_host ne $server ) {
          PTDEBUG && _d('Packet is not to or from', $server);
-         return;
+         return $self->{null_event};
       }
    }
 
@@ -3825,7 +3831,7 @@ sub parse_event {
    }
    else {
       PTDEBUG && _d('Packet is not to or from a MySQL server');
-      return;
+      return $self->{null_event};
    }
    PTDEBUG && _d('Client', $client);
 
@@ -3843,7 +3849,7 @@ sub parse_event {
       else {
          PTDEBUG && _d('Ignoring mid-stream', $packet_from, 'data,',
             'packetno', $packetno);
-         return;
+         return $self->{null_event};
       }
 
       $self->{sessions}->{$client} = {
@@ -3886,7 +3892,7 @@ sub parse_event {
          delete $self->{sessions}->{$session->{client}};
          return $event;
       }
-      return;
+      return $self->{null_event};
    }
 
    if ( $session->{compress} ) {
@@ -3912,7 +3918,7 @@ sub parse_event {
          PTDEBUG && _d('remove_mysql_header() failed; failing session');
          $session->{EVAL_ERROR} = $EVAL_ERROR;
          $self->fail_session($session, 'remove_mysql_header() failed');
-         return;
+         return $self->{null_event};
       }
    }
 
@@ -3927,7 +3933,7 @@ sub parse_event {
             $self->_delete_buff($session);
          }
          else {
-            return;  # waiting for more data; buff_left was reported earlier
+            return $self->{null_event};  # waiting for more data; buff_left was reported earlier
          }
       }
       elsif ( $packet->{mysql_data_len} > ($packet->{data_len} - 4) ) {
@@ -3948,7 +3954,7 @@ sub parse_event {
 
          PTDEBUG && _d('Data not complete; expecting',
             $session->{buff_left}, 'more bytes');
-         return;
+         return $self->{null_event};
       }
 
       if ( $session->{cmd} && ($session->{state} || '') eq 'awaiting_reply' ) {
@@ -3971,7 +3977,7 @@ sub parse_event {
    }
 
    $args{stats}->{events_parsed}++ if $args{stats};
-   return $event;
+   return $event || $self->{null_event};
 }
 
 sub _packet_from_server {
@@ -9831,7 +9837,15 @@ sub _get_errors_fh {
    return $self->{errors_fh} if $self->{errors_fh};
 
    my $exec = basename($0);
-   my ($errors_fh, $filename) = tempfile("/tmp/$exec-errors.XXXXXXX", UNLINK => 0);
+   my ($errors_fh, $filename);
+   if ( $filename = $ENV{PERCONA_TOOLKIT_TCP_ERRORS_FILE} ) {
+      open $errors_fh, ">", $filename
+         or die "Cannot open $filename for writing (supplied from "
+              . "PERCONA_TOOLKIT_TCP_ERRORS_FILE): $OS_ERROR";
+   }
+   else {
+      ($errors_fh, $filename) = tempfile("/tmp/$exec-errors.XXXXXXX", UNLINK => 0);
+   }
 
    $self->{errors_file} = $filename;
    $self->{errors_fh}   = $errors_fh;
@@ -9847,7 +9861,8 @@ sub fail_session {
 
    my $errors_fh = $self->_get_errors_fh();
 
-   print "Session $session->{client} had errors, will save them in $self->{errors_file}\n";
+   warn "TCP session $session->{client} had errors, will save them in $self->{errors_file}\n"
+      unless $self->{_warned_for}->{$self->{errors_file}}++;
 
    my $raw_packets = delete $session->{raw_packets};
    $session->{reason_for_failure} = $reason;
diff --git a/bin/pt-upgrade b/bin/pt-upgrade
index 6ed1f93e..ec1ad261 100755
--- a/bin/pt-upgrade
+++ b/bin/pt-upgrade
@@ -78,6 +78,7 @@ our $VERSION = '2.2.1';
 # ###########################################################################
 {
 package Lmo::Utils;
+
 use strict;
 use warnings qw( FATAL all );
 require Exporter;
@@ -85,7 +86,12 @@ our (@ISA, @EXPORT, @EXPORT_OK);
 
 BEGIN {
    @ISA = qw(Exporter);
-   @EXPORT = @EXPORT_OK = qw(_install_coderef _unimport_coderefs _glob_for _stash_for);
+   @EXPORT = @EXPORT_OK = qw(
+      _install_coderef
+      _unimport_coderefs
+      _glob_for
+      _stash_for
+   );
 }
 
 {
@@ -269,7 +275,6 @@ sub meta {
    return Lmo::Meta->new(class => $class);
 }
 
-
 1;
 }
 # ###########################################################################
@@ -7309,7 +7314,15 @@ sub _get_errors_fh {
    return $self->{errors_fh} if $self->{errors_fh};
 
    my $exec = basename($0);
-   my ($errors_fh, $filename) = tempfile("/tmp/$exec-errors.XXXXXXX", UNLINK => 0);
+   my ($errors_fh, $filename);
+   if ( $filename = $ENV{PERCONA_TOOLKIT_TCP_ERRORS_FILE} ) {
+      open $errors_fh, ">", $filename
+         or die "Cannot open $filename for writing (supplied from "
+              . "PERCONA_TOOLKIT_TCP_ERRORS_FILE): $OS_ERROR";
+   }
+   else {
+      ($errors_fh, $filename) = tempfile("/tmp/$exec-errors.XXXXXXX", UNLINK => 0);
+   }
 
    $self->{errors_file} = $filename;
    $self->{errors_fh}   = $errors_fh;
@@ -7325,7 +7338,8 @@ sub fail_session {
 
    my $errors_fh = $self->_get_errors_fh();
 
-   print "Session $session->{client} had errors, will save them in $self->{errors_file}\n";
+   warn "TCP session $session->{client} had errors, will save them in $self->{errors_file}\n"
+      unless $self->{_warned_for}->{$self->{errors_file}}++;
 
    my $raw_packets = delete $session->{raw_packets};
    $session->{reason_for_failure} = $reason;
diff --git a/lib/ProtocolParser.pm b/lib/ProtocolParser.pm
index 15678f99..38fcacb3 100644
--- a/lib/ProtocolParser.pm
+++ b/lib/ProtocolParser.pm
@@ -252,7 +252,15 @@ sub _get_errors_fh {
 
    my $exec = basename($0);
    # Errors file isn't open yet; try to open it.
-   my ($errors_fh, $filename) = tempfile("/tmp/$exec-errors.XXXXXXX", UNLINK => 0);
+   my ($errors_fh, $filename);
+   if ( $filename = $ENV{PERCONA_TOOLKIT_TCP_ERRORS_FILE} ) {
+      open $errors_fh, ">", $filename
+         or die "Cannot open $filename for writing (supplied from "
+              . "PERCONA_TOOLKIT_TCP_ERRORS_FILE): $OS_ERROR";
+   }
+   else {
+      ($errors_fh, $filename) = tempfile("/tmp/$exec-errors.XXXXXXX", UNLINK => 0);
+   }
 
    $self->{errors_file} = $filename;
    $self->{errors_fh}   = $errors_fh;
@@ -268,7 +276,8 @@ sub fail_session {
 
    my $errors_fh = $self->_get_errors_fh();
 
-   print "Session $session->{client} had errors, will save them in $self->{errors_file}\n";
+   warn "TCP session $session->{client} had errors, will save them in $self->{errors_file}\n"
+      unless $self->{_warned_for}->{$self->{errors_file}}++;
 
    my $raw_packets = delete $session->{raw_packets};
    $session->{reason_for_failure} = $reason;
diff --git a/t/lib/MySQLProtocolParser.t b/t/lib/MySQLProtocolParser.t
index b2422435..8f5d3b60 100644
--- a/t/lib/MySQLProtocolParser.t
+++ b/t/lib/MySQLProtocolParser.t
@@ -1759,14 +1759,14 @@ my $out = output(sub {
          $protocol->parse_event(%parser_args, event => $p);
       }
       close $fh;
-});
+}, stderr => 1);
 
 like(
    $out,
    qr/had errors, will save them in /,
    "Saves errors by default"
 );
-
+      
 close $protocol->{errors_fh}; # flush the handle
 
 like(
@@ -1775,6 +1775,53 @@ like(
    "The right error is saved"
 );
 
+$out = output(sub {
+      open my $fh, "<", "$sample/tcpdump032.txt" or die "Cannot open tcpdump032.txt: $OS_ERROR";
+      my %parser_args = (
+         next_event => sub { return <$fh>; },
+         tell       => sub { return tell($fh);  },
+      );
+      while ( my $p = $tcpdump->parse_event(%parser_args) ) {
+         $protocol->parse_event(%parser_args, event => $p);
+      }
+      close $fh;
+}, stderr => 1);
+
+is(
+   $out,
+   '',
+   "No warnings the second time around"
+);
+      
+{
+$protocol = new MySQLProtocolParser(server=>'127.0.0.1',port=>'3306');
+# ..but allow setting the filename through an ENV var:
+local $ENV{PERCONA_TOOLKIT_TCP_ERRORS_FILE} = '/dev/null';
+
+$out = output(sub {
+      open my $fh, "<", "$sample/tcpdump032.txt" or die "Cannot open tcpdump032.txt: $OS_ERROR";
+      my %parser_args = (
+         next_event => sub { return <$fh>; },
+         tell       => sub { return tell($fh);  },
+      );
+      while ( my $p = $tcpdump->parse_event(%parser_args) ) {
+         $protocol->parse_event(%parser_args, event => $p);
+      }
+      close $fh;
+}, stderr => 1);
+
+like(
+   $out,
+   qr/had errors, will save them in /,
+   "Still tries saving the errors with PERCONA_TOOLKIT_TCP_ERRORS_FILE"
+);
+
+is(
+   $protocol->{errors_file},
+   '/dev/null',
+   "...but uses the provided file"
+);
+}
 # #############################################################################
 # Done.
 # #############################################################################