#! /bin/bash
# Script will be excuted by tcpdump -z option

og_filename="$1"
timestamp=$(stat -c %Y "$og_filename")
compressed_filename="${og_filename}_${timestamp}.pcap.zst"

# If compressed file exist with same base as og file, it means tcpdump rotate made one turn
# So delete it manually as tcppdump is not aware of compressed file
rm -f "${og_filename}"*.pcap.zst

# Compress og file and delete it
zstd "$og_filename" -o "$compressed_filename" --rm