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

Posted by Felipe Alvarez on Stack Overflow See other posts from Stack Overflow or by Felipe Alvarez
Published on 2010-06-06T05:32:46Z Indexed on 2010/06/06 5:42 UTC
Read the original article Hit count: 282

Filed under:

shell

|

shell-scripting

|

loops

|

while-loops

#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]="$line"
  c=$((c+1))  
done < all.txt

The following fails to work.

# I would prefer something like...
#
pcap="somefile.pcap"
while read line; do  
  ARRAY[$c]="$line"
  c=$((c+1))  
done < $( tcpdump -n -r "$pcap" )

Too few results on Google (doesn't understand what I want to find :( ). I'd like to keep it Bourne-compatible (/bin/sh), but it doesn't have to be.

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