Improve packet display formatting in test_monitor_tshark.sh

- Replace raw tab-separated values with readable format
- Show 'Frame X: PLCP header (radiotap) = yes/no' instead of '1 1'
- Add field labels for main capture sample packets
- Show SA, DA, type, subtype, and PLCP status in readable format

Co-authored-by: Cursor <cursoragent@cursor.com>

test_monitor_tshark.sh

@@ -97,10 +97,13 @@ PACKET_COUNT=$(echo "$PACKET_LINES" | wc -l || echo "0")
 # Count lines with both frame.number and radiotap.present (non-empty second field)
 PLCP_COUNT=$(echo "$PACKET_LINES" | awk -F'\t' 'NF >= 2 && $1 != "" && $2 != "" && $2 != "0" && $2 != "-" {count++} END {print count+0}' || echo "0")
 
-# Show sample output
+# Show sample output with better formatting
 if [ "$PACKET_COUNT" -gt 0 ]; then
     echo "Sample packets:"
-    echo "$PACKET_LINES" | head -3
+    echo "$PACKET_LINES" | head -5 | awk -F'\t' '{
+        radiotap = ($2 == "1" || $2 == "1.0") ? "yes" : "no"
+        printf "  Frame %s: PLCP header (radiotap) = %s\n", $1, radiotap
+    }'
 fi
 
 echo ""
@@ -119,7 +122,7 @@ echo ""
 # Capture for specified duration and count packets
 echo "Capturing packets for $DURATION seconds..."
 
-# Run capture in background and show progress
+# Run capture with timeout
 CAPTURE_OUTPUT=$(timeout "$DURATION" tshark -i "$INTERFACE" -n -T fields \
     -e frame.number \
     -e frame.time \
@@ -132,25 +135,30 @@ CAPTURE_OUTPUT=$(timeout "$DURATION" tshark -i "$INTERFACE" -n -T fields \
     2>&1)
 CAPTURE_EXIT_CODE=$?
 
-# Immediately show stats after capture completes
+# Force output flush
+sync
+
+# Show stats immediately after capture completes
 echo ""
 echo "=== Capture Statistics ==="
 
-# Show any warnings/errors
-WARNINGS=$(echo "$CAPTURE_OUTPUT" | grep -E "(tshark:|Warning|Error)" | head -5 || true)
+# Show any warnings/errors (but not the "Running as root" or "Capturing" messages)
+WARNINGS=$(echo "$CAPTURE_OUTPUT" | grep -E "(tshark:|Warning|Error)" | grep -v -E "(Running as|Capturing)" | head -5 || true)
 if [ -n "$WARNINGS" ]; then
     echo "$WARNINGS"
+    echo ""
 fi
 
-# Count total packets captured (lines starting with a number)
-PACKET_LINES=$(echo "$CAPTURE_OUTPUT" | grep -E '^[0-9]+' || true)
+# Count total packets captured (lines starting with a number followed by tab)
+# Filter out lines like "100 packets captured" which don't have tabs
+PACKET_LINES=$(echo "$CAPTURE_OUTPUT" | grep -E '^[0-9]+\t' || true)
 FINAL_COUNT=$(echo "$PACKET_LINES" | wc -l || echo "0")
 
 # Count packets with PLCP headers (radiotap present)
 # radiotap.present field is the 8th field (after frame.number, frame.time, wlan.sa, wlan.da, wlan.fc.type, wlan.fc.subtype, wlan.fc.type_subtype)
 PLCP_COUNT=$(echo "$PACKET_LINES" | awk -F'\t' 'NF >= 8 && $1 != "" && $8 != "" && $8 != "0" && $8 != "-" {count++} END {print count+0}' || echo "0")
 
-# Display stats immediately
+# Display stats immediately - always show these
 echo "Total packets captured: $FINAL_COUNT"
 echo "PLCP headers: $PLCP_COUNT"
 if [ "$FINAL_COUNT" -gt 0 ]; then
@@ -160,10 +168,18 @@ if [ "$FINAL_COUNT" -gt 0 ]; then
 fi
 echo ""
 
-# Display sample packets
+# Display sample packets with readable format
 if [ -n "$PACKET_LINES" ] && [ "$FINAL_COUNT" -gt 0 ]; then
-    echo "Sample packets (first 20):"
-    echo "$PACKET_LINES" | head -20
+    echo "Sample packets (first 10):"
+    echo "$PACKET_LINES" | head -10 | awk -F'\t' '{
+        sa = ($3 != "" && $3 != "-") ? $3 : "N/A"
+        da = ($4 != "" && $4 != "-") ? $4 : "N/A"
+        type = ($5 != "" && $5 != "-") ? $5 : "N/A"
+        subtype = ($6 != "" && $6 != "-") ? $6 : "N/A"
+        radiotap = ($8 == "1" || $8 == "1.0") ? "yes" : (($8 != "" && $8 != "-") ? "no" : "N/A")
+        printf "  Frame %s: SA=%s, DA=%s, type=%s/%s, PLCP=%s\n",
+            $1, sa, da, type, subtype, radiotap
+    }'
     echo ""
 else
     echo "(No packets captured)"