2004/10/24 cmp

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© October 2004 Tony Lawrence

I often forget about "cmp" and use "diff" when all I really want to know is if two files are the same:

cmp -s file1 file2 || echo "Not the same"

Often the reason for the comparison is that I've written something like this:

touch /tmp/testdirb.$$
while :
do
  ls /testdir > /tmp/testdira.$$
  cmp -s /tmp/testdira.$$ /tmp/testdirb.$$ || echo "changed"
  cp /tmp/testdira.$$ /tmp/testdirb.$$
  sleep 300
done
 

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