>>>>> "M" == Max Ischenko <max / malva.com.ua> writes:

M> It works, but do not make changes to the file itself.

 Sorry, I've not understood.

 You can't make a modification to a file if you don't save the result,
 i.e. you must first open a new file, then
  * read a line
  * modify it
  * write the line to the new file
  * continue until you reach the end of the file

 This is what do the switch -i and -p in perl and ruby.



Guy Decoux