diff --git a/check_uptime.sh b/check_uptime.sh
index 62382ee..b5ae57e 100755
--- a/check_uptime.sh
+++ b/check_uptime.sh
@@ -1,26 +1,25 @@
-#!/usr/bin/env bash
+#!/bin/bash
 
-# Get the uptime start time
-UPTIME_OUTPUT=$(uptime -s)
-UPTIME_EXIT_CODE=$?
-
-# Check if the uptime command was successful
-if [ $UPTIME_EXIT_CODE -ne 0 ]; then
-  echo "UNKNOWN - Unable to get uptime"
-  exit -1
+# Check if the system is Linux or BSD
+# if [[ "$(uname)" == "Linux" ]]; then
+#   # Get uptime in seconds for Linux
+#   total_uptime_seconds=$(cat /proc/uptime | awk '{print $1}')
+if uname | grep -q "BSD"; then
+  # Get uptime in seconds for BSD
+  boot_time_seconds=$(sysctl -n kern.boottime | awk -F'[ ,]' '{print $4}')
+  total_uptime_seconds=$(($(date +%s) - boot_time_seconds))
+else
+  total_uptime_seconds=$(cat /proc/uptime | awk '{print $1}')
+  # echo "UNKNOWN: Unsupported system"
+  # exit 3
 fi
 
-# Calculate the uptime in seconds
-UPTIME_START=$(date -u -d "$UPTIME_OUTPUT" +%s)
-CURRENT_TIME=$(date -u +%s)
-UPTIME_SECONDS=$((CURRENT_TIME - UPTIME_START))
+# Calculate uptime in days, hours, minutes, and seconds
+uptime_days=$((total_uptime_seconds / 86400))
+uptime_hours=$(( (total_uptime_seconds % 86400) / 3600 ))
+uptime_minutes=$(( (total_uptime_seconds % 3600) / 60 ))
+uptime_seconds=$((total_uptime_seconds % 60))
 
-# Convert the uptime seconds to hours
-UPTIME_HOURS=$(echo "scale=2; $UPTIME_SECONDS / 3600" | bc)
-
-# Convert the uptime seconds to days
-UPTIME_DAYS=$(echo "scale=2; $UPTIME_SECONDS / 86400" | bc)
-
-# Print the result and performance data
-echo "OK - Uptime: $UPTIME_DAYS days | uptime_hours=$UPTIME_HOURS"
+# Print the result and perfdata
+echo "OK: Uptime is ${uptime_days}d ${uptime_hours}h ${uptime_minutes}m ${uptime_seconds}s | total_uptime_seconds=${total_uptime_seconds}s;"
 exit 0