The below code does the trick with one small problem left to be solved import shutil import string
currentdata_file = r"C:\Users\Owner\Desktop\newdata.txt" # the current download from the clock lastdata_file = r"C:\Users\Owner\Desktop\mydata.txt" # the prior download from the clock output_file = r"C:\Users\Owner\Desktop\out.txt" # will hold delta clock data shutil.copy(currentdata_file, output_file) f = open(lastdata_file, 'r') read_data1 = f.read() f.close() f = open(currentdata_file, 'r') read_data2 = f.read() f.close() replaceText = '' file = open(output_file, 'w') file.write(string.replace(read_data2, read_data1, replaceText)) file.close() Contents of lastdata_file: AU08JEDD011485H14472402210 AU08JEDD020163C14472502210 AU08JEDD005029C14480102210 AU08JEDD004923H14482002210 AU08AWOL000799H14483902210 Contents of currentdata_file: AU08JEDD011485H14472402210 AU08JEDD020163C14472502210 AU08JEDD005029C14480102210 AU08JEDD004923H14482002210 AU08AWOL000799H14483902210 AU08AWOL000120H14495902210 AU08ARPU050241H14511702210 IF08DRTO008074H14520202210 IF08DRTO008089H14521102210 IF08DRTO008077H14553602210 IF08CHES000023H14594902210 Contents of output_file: AU08AWOL000120H14495902210 AU08ARPU050241H14511702210 IF08DRTO008074H14520202210 IF08DRTO008089H14521102210 IF08DRTO008077H14553602210 IF08CHES000023H14594902210 output_file has a blank line at the top because of replaceText = '' Is there something besides '' that I can use to not end up with a blank line at the top of output_file, or what is the code to delete the first line of that file? Thanks -- http://mail.python.org/mailman/listinfo/python-list
