HI, My file contains the data like john smitch Tracy -tcopse I have to add a new string "PETER"at the 4th posion so the file shud contain the data like: john smitch Tracy PETER -tcopse please lemme know how it can be done...

One of the other guys will give you an awk or perl solution, but this one uses the shell: #!/bin/ksh newvar="PETER" while read f1 f2 f3 fr do echo "f1 $f2 $f3 $newvar $fr" done < file.txt

This statement helps you to add a new string in a file. cat filename | awk '{print $1,$2,$3,"PETER",$4}' >Output Thanks Rajam

Rajam: Your awk script works only for lines with 4 fields. If more the 4 fields exist, then the fields need to be shifted. (My original shell solution doesn't have this issue). This script works for any number of fields: #!/bin/ksh awk ' BEGIN { pos=4; newvar="PETER" } { for(i=1;i<=NF;i++) { if (i == pos) { savevar=$pos $pos=newvar } if (i > pos) { buffer=$i $i=savevar savevar=buffer } if (i == NF) savestr=$0" "savevar } print savestr } ' filename

Thnx alot Nails...this is what i was looking for...