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Date: Wed, 5 May 2010 18:25:44 -0700
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From: Evuraan <evuraan@gmail.com>
To: Paul Hoffman <phoffman@proper.com>
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Cc: freebsd-questions@freebsd.org
Subject: bash while read question
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I cant figure out why the variable in in loop2 does not hike to +1?
(its a friday, i am dazed, I admit. but this should not be a mystery!)
any help would be much appreciated.


$ cat loop1
#! /bin/bash

date > /tmp/somefile
b="1"
while read blah; do
let b=(b+1)
done  < /tmp/somefile
echo "variable is $b"

$ cat loop2
#! /bin/bash

date > /tmp/somefile
b="1"
cat /tmp/somefile | while read blah; do
let b=(b+1)
done
echo "variable is $b"


$ ./loop1
variable is 2

$ ./loop2
variable is 1