input of while loop to come from output of `command`

Question

#I used to have this, but I don\'t want to write to the disk
#
pcap=\"somefile.pcap\"
tcpdump -n -r $pcap > all.txt
while read line; do  
  ARRAY[$c]=\"$line\"
  c=$(         


        

Answer 1

This is sh-compatible:

tcpdump -n -r "$pcap" | while read line; do  
  # something
done

However, sh does not have arrays, so you can't have your code like it is in sh. Others are correct in saying both bash and perl are nowadays rather widespread, and you can mostly count on their being available on non-ancient systems.

UPDATE to reflect @Dennis's comment