#!/usr/bin/env python3
# Extract the list of interfaces available for traffic dumps from tcpdump -D
import re
import subprocess
if __name__ == '__main__':
out = subprocess.check_output(['/usr/sbin/tcpdump', '-D']).decode().strip()
out = out.split("\n")
intfs = " ".join(map(lambda s: re.search(r'\d+\.(\S+)\s', s).group(1), out))
print(intfs)