diff --git a/plugins/assp/assp-envelope-recipient-statistics b/plugins/assp/assp-envelope-recipient-statistics
index e21af08b..d5062bb2 100755
--- a/plugins/assp/assp-envelope-recipient-statistics
+++ b/plugins/assp/assp-envelope-recipient-statistics
@@ -66,7 +66,7 @@ my @muninlabel = (
 );
 
 # ============= SANITY CHECKS ================
-unless( defined(@ARGV) ){
+unless( @ARGV ){
 	$ARGV[0] = "";
 }
 
diff --git a/plugins/assp/assp-general-runtime-information b/plugins/assp/assp-general-runtime-information
index 32aa0349..a8535373 100755
--- a/plugins/assp/assp-general-runtime-information
+++ b/plugins/assp/assp-general-runtime-information
@@ -46,7 +46,7 @@ my @muninlabel = (													# General Runtime Information
 );
 
 # ============= SANITY CHECKS ================
-unless( defined(@ARGV) ){
+unless( @ARGV ){
 	$ARGV[0] = "";
 }
 
diff --git a/plugins/assp/assp-message-statistics b/plugins/assp/assp-message-statistics
index 78032338..92b1c667 100755
--- a/plugins/assp/assp-message-statistics
+++ b/plugins/assp/assp-message-statistics
@@ -78,7 +78,7 @@ my @muninlabel = (
 );
 
 # ============= SANITY CHECKS ================
-unless( defined(@ARGV) ){
+unless( @ARGV ){
 	$ARGV[0] = "";
 }
 
diff --git a/plugins/assp/assp-smtp-connection-statistics b/plugins/assp/assp-smtp-connection-statistics
index ddddd1e0..a41f9f21 100755
--- a/plugins/assp/assp-smtp-connection-statistics
+++ b/plugins/assp/assp-smtp-connection-statistics
@@ -56,7 +56,7 @@ my @muninlabel = (
 );
 
 # ============= SANITY CHECKS ================
-unless( defined(@ARGV) ){
+unless( @ARGV ){
 	$ARGV[0] = "";
 }
 
diff --git a/plugins/assp/assp-smtp-handler-statistics b/plugins/assp/assp-smtp-handler-statistics
index c80e5083..3041b481 100755
--- a/plugins/assp/assp-smtp-handler-statistics
+++ b/plugins/assp/assp-smtp-handler-statistics
@@ -46,7 +46,7 @@ my @muninlabel = (													# General Runtime Information
 );
 
 # ============= SANITY CHECKS ================
-unless( defined(@ARGV) ){
+unless( @ARGV ){
 	$ARGV[0] = "";
 }
 
diff --git a/plugins/quake/qstat b/plugins/quake/qstat
index d0657b0d..32c645c6 100755
--- a/plugins/quake/qstat
+++ b/plugins/quake/qstat
@@ -60,7 +60,7 @@ quake_stat() {
 		port=$3
 	fi
 
-	if [ ! -z "$gametype" ] && [ ! -z "$gametype" ] && [ ! -z "$gametype" ]; then
+	if [ -n "$gametype" ] && [ -n "$gametype" ] && [ -n "$gametype" ]; then
 		dummy=$("$qstat_exe" -raw ";" -nh "-$gametype" "${ip}:${port}")
 
 		playervalue=$(echo "$dummy" | cut -d\; -f6)
diff --git a/plugins/quake/qstatet_ b/plugins/quake/qstatet_
index d792f235..8e68ad34 100755
--- a/plugins/quake/qstatet_
+++ b/plugins/quake/qstatet_
@@ -60,7 +60,7 @@ quake_stat() {
 		port=$3
 	fi
 
-	if [ ! -z "$gametype" ] && [ ! -z "$gametype" ] && [ ! -z "$gametype" ]; then
+	if [ -n "$gametype" ] && [ -n "$gametype" ] && [ -n "$gametype" ]; then
 		stat_output=$("$qstat_exe" -P -pa -sort P "-$gametype" "${ip}:${port}" | grep frags)
 		playervalue=$(echo "$stat_output" | grep -cwv 0ms)
 		maxplayervalue=$(echo "$stat_output" | grep -cw 0ms)
diff --git a/plugins/quake/qstatqw_ b/plugins/quake/qstatqw_
index df29156d..908b95f4 100755
--- a/plugins/quake/qstatqw_
+++ b/plugins/quake/qstatqw_
@@ -60,7 +60,7 @@ quake_stat() {
 		port=$3
 	fi
 
-	if [ ! -z "$gametype" ] && [ ! -z "$gametype" ] && [ ! -z "$gametype" ]; then
+	if [ -n "$gametype" ] && [ -n "$gametype" ] && [ -n "$gametype" ]; then
 		stat_output=$("$qstat_exe" -P -pa -sort P "-${gametype}" "${ip}:${port}" | grep team)
 		playervalue=$(echo "$stat_output" | grep -cwv 0ms)
 		maxplayervalue=$(echo "$stat_output" | grep -cw 0ms)
diff --git a/plugins/sensors/allnet__ b/plugins/sensors/allnet__
index dcd70a6d..feec5c13 100755
--- a/plugins/sensors/allnet__
+++ b/plugins/sensors/allnet__
@@ -166,7 +166,7 @@ if (defined($ENV{'beextratolerant'})) {
   }
 }
 #print($sensordata->[0]);
-foreach $k (keys($sensordata)) {
+foreach $k (keys(%$sensordata)) {
   if ($k =~ m/^n(\d+)$/) { # Special handling: Could be output from the OLD XML interface.
     my $nr = $1;
     if (defined($sensordata->{'s'.$nr})