#! /bin/ksh
typeset    fInput="/data/m/b.csc"      # input filename
typeset    fOutput="/data/o/tran.csv"  # output filename

if [ -r "$fInput" ] ; then     # perhaps there should be more input validation
     print -u2 "unable to read input file"
     exit 1
fi

sed 's/^\([^,]*,[^,]*,[^,]*,\)\([0-9]\{1,5\}\),/\1000\2/
     s/^\([^,]*,\)[^,]*,\([^,]*,[^,]*,[^,]*,\)[^,]*,\([^,]*\).*$/\1\2\3/' $fInput > $fOutput

exit $?