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#!/bin/bash
# This is an alternate form of the preceding script.
# Suggested by Heiner Steven
#+ as a workaround in those situations when a redirect loop
#+ runs as a subshell, and therefore variables inside the loop
# +do not keep their values upon loop termination.
if [ -z "$1" ]
then
Filename=names.data # Default, if no filename specified.
else
Filename=$1
fi
exec 3<&0 # Save stdin to file descriptor 3.
exec 0<"$Filename" # Redirect standard input.
count=0
echo
while [ "$name" != Smith ]
do
read name # Reads from redirected stdin ($Filename).
echo $name
let "count += 1"
done # Loop reads from file $Filename
#+ because of line 20.
# The original version of this script terminated the "while" loop with
#+ done <"$Filename"
# Exercise:
# Why is this unnecessary?
exec 0<&3 # Restore old stdin.
exec 3<&- # Close temporary fd 3.
echo; echo "$count names read"; echo
exit 0
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