Shell Programming and Scripting

+ REPL='U N I X' 
shift
+ shift

for FILE in $*
do
        mv $FILE $FILE.txt
        sed "s/$PAT/$REPL/g" $FILE.txt > $FILE
done
+ FILE=_king
+ mv _king _king.txt
+ sed 's/Unix/U N I X/g' _king.txt
+ FILE=cobra.dat
+ mv cobra.dat cobra.dat.txt
+ sed 's/Unix/U N I X/g' cobra.dat.txt
+ FILE=_ne$wt.foo
+ mv '_ne$wt.foo' '_ne$wt.foo.txt'
+ sed 's/Unix/U N I X/g' '_ne$wt.foo.txt'

#!/bin/ksh
set -xv
PAT=$1
shift
REPL=$1
shift

for FILE in $*
do
	mv "$FILE" "$FILE.bak"
	sed "s/$PAT/$REPL/g" "$FILE.bak" > "$FILE"
done

Incorrect output on test 33: /home/sub3 'Unix' 'U N I X' '_king cobra.dat' '_ne$wt.foo'