Shell Programming and Scripting

#! /usr/bin/ksh

DATA=data
OLD=old
NEW=new
TMP=repfiletmp$$


target1=$(sed 1q < $OLD)
targetnum=$(wc -l < $OLD)
echo target: $targetnum $target1
echo tmpfile = $TMP


exec < $DATA
IFS=""
while read line ; do
        if [[ $line = $target1 ]] ; then
                tmpct=1
                echo $line > $TMP
                while ((tmpct<targetnum)) ; do
                        read line && echo $line >> $TMP
                        ((tmpct=tmpct+1))
                done
                if cmp -s $OLD $TMP ; then
                        cat $NEW
                else
                        cat $TMP
                fi
                rm $TMP

        else
                echo $line
        fi
done

exit 0

perl -e '
   undef $/;
   open(SEAR, "< exfile2");
   open(REPL, "< exfile3");
   open(INFI, "< exfile1");
   open(OUTF, "> exfile4");
   $sear = <SEAR>;
   $repl = <REPL>;
   $data = <INFI>;
   $data =~ s/$sear/$repl/g;
   print OUTF $data;
'

DATA=ain.ps
OLD=aold.ps
NEW=anew.ps
OUT=aout.ps
rm -f $OUT

TMP=repfiletmp$$
target1=$(sed 1q < $OLD)
targetnum=$(wc -l < $OLD)
echo target: $targetnum $target1
echo tmpfile = $TMP

exec < $DATA
IFS=""
while read -r line ; do
        if [[ $line = $target1 ]] ; then
                tmpct=1
                print -r -- "$line" > $TMP
                while ((tmpct<targetnum)) ; do
                        read -r line && print -r -- "$line" >> $TMP
                        ((tmpct=tmpct+1))
                done
                if cmp -s $OLD $TMP ; then
                        cat $NEW >> $OUT
                else
                        cat $TMP >> $OUT
                fi
                rm $TMP
        else
                print -r -- "$line" >> $OUT
        fi
done
exit 0