Output to the same line overwriting previous output

Question

I am writing an FTP downloader  Part of to the code is something like this   ftp retrbinary  RETR     file name  process    I am calling function process to handle the callback   def process data       print os path getsize file name  1024   KB      size   KB downloaded       file write data    and output is something like this   1784  KB   KB 1829 downloaded  1788  KB   KB 1829 downloaded  etc         but I want it to print this line and next time reprint refresh it so it will only show it once and I will see progress of that download   How can it be done

User · Answer

Here s my little class that can reprint blocks of text  It properly clears the previous text so you can overwrite your old text with shorter new text without creating a mess   import re  sys  class Reprinter      def   init   self           self text           def moveup self  lines           for   in range lines               sys stdout write   x1b A        def reprint self  text             Clear previous text by overwritig non-spaces with spaces         self moveup self text count   n            sys stdout write re sub r    s         self text              Print new text         lines   min self text count   n    text count   n            self moveup lines          sys stdout write text          self text   text  reprinter   Reprinter    reprinter reprint  Foobar nBazbar   reprinter reprint  Foo nbar

User · Answer

Have a look at the curses module documentation and the curses module HOWTO   Really basic example   import time import curses  stdscr   curses initscr    stdscr addstr 0  0   Hello   stdscr refresh    time sleep 1   stdscr addstr 0  0   World   with curses    stdscr refresh

User · Answer

I found that for a simple print statement in python 2 7  just put a comma at the end after your   r    print os path getsize file name  1024   KB      size   KB downloaded  r     This is shorter than other non-python 3 solutions  but also more difficult to maintain

User · Answer

to overwiting the previous line in python all wath you need is to add end   r  to the print function  test this example   import time for j in range 1 5      print  waiting     j  end   r      time sleep 1

User · Answer

I am using spyder 3 3 1 - windows 7 - python 3 6 although flush may not be needed  based on this posting - https   github com spyder-ide spyder issues 3437      works in spyder ipython console -  r at start of string   end    import time import sys     for i in range 20           time sleep 0 5          print f  rnumber i   end             sys stdout flush

User · Answer

If all you want to do is change a single line  use  r   r means carriage return  It s effect is solely to put the caret back at the start of the current line  It does not erase anything  Similarly   b can be used to go one character backward   some terminals may not support all those features   import sys  def process data       size str   os path getsize file name  1024   KB      size   KB downloaded       sys stdout write   s r    size str      sys stdout flush       file write data

User · Answer

You can just add   r  at the end of the string plus a comma at the end of print function  For example   print os path getsize file name  1024  KB     size   KB downloaded  r

User · Answer

Here s code for Python 3 x   print os path getsize file name  1024  KB     size   KB downloaded    end   r     The end  keyword is what does the work here -- by default  print   ends in a newline   n  character  but this can be replaced with a different string  In this case  ending the line with a carriage return instead returns the cursor to the start of the current line  Thus  there s no need to import the sys module for this sort of simple usage  print   actually has a number of keyword arguments which can be used to greatly simplify code   To use the same code on Python 2 6   put the following line at the top of the file   from   future   import print function

[python] Output to the same line overwriting previous output?

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