diff --git a/check_pg_streaming_replication b/check_pg_streaming_replication
index 3023d37..ae746a3 100755
--- a/check_pg_streaming_replication
+++ b/check_pg_streaming_replication
@@ -120,6 +120,12 @@ function psql_get () {
 	echo "$sql"|su - $PG_USER -c "$PSQL_BIN -d "$PG_DB" -w -t -P format=unaligned"
 }
 
+function psql_master_get () {
+	sql="$1"
+	debug "Exec 'echo \"$sql\"|su - $PG_USER -c \"$PSQL_BIN -U $M_USER -h $M_HOST -w -p $M_PORT -d $PG_DB -t -P format=unaligned\""
+	echo "$sql"|su - $PG_USER -c "$PSQL_BIN -U $M_USER -h $M_HOST -w -p $M_PORT -d $PG_DB -t -P format=unaligned"
+}
+
 function debug() {
 	if [ $DEBUG -eq 1 ]
 	then
@@ -211,7 +217,7 @@ then
 	fi
 	
 	# Get current xlog file from master
-	M_CUR_XLOG="$( echo 'SELECT pg_current_xlog_location()'|su - $PG_USER -c "$PSQL_BIN -U $M_USER -h $M_HOST -p $M_PORT -d $PG_DB -t -P format=unaligned" )"
+	M_CUR_XLOG="$( psql_master_get 'SELECT pg_current_xlog_location()' )"
 	if [ ! -n "$M_CUR_XLOG" ]
 	then
 		echo "UNKNOWN : Can't retreive current xlog from master server"