run tcpdump to capture chrome activity

gistfile1.txt

#!/bin/zsh
# This script uses apple-specific features of tcpdump

INT=en0
PIDS=($(pgrep Chrome | tr '\n' ' '))                                 
PID_FILTER=$(echo pid=${(j: or pid=:)PIDS})
FILTER="-Q \"$(echo -n "if=${INT} and ("${PID_FILTER}))\""
OUT=$(mktemp)
CMD="/usr/bin/sudo /usr/sbin/tcpdump -i pktap,${INT} -s0 -w ${OUT} -nk ${FILTER}"
echo "Capturing to ${OUT} with command:\n${CMD}"
eval ${CMD}