How do I write output in same place on the console?

Question

I am new to python and am writing some scripts to automate downloading files from FTP servers, etc. I want to show the progress of the download, but I want it to stay in the same position, such as:

output:

Downloading File FooFile.txt [47%]

I'm trying to avoid something like this:

     Downloading File FooFile.txt [47%]
     Downloading File FooFile.txt [48%]
     Downloading File FooFile.txt [49%]

How should I go about doing this?

---

Duplicate: How can I print over the current line in a command line application?

Solution 1

You can also use the carriage return:

sys.stdout.write("Download progress: %d%%   \r" % (progress) )
sys.stdout.flush()

Solution 2

Python 2

I like the following:

print 'Downloading File FooFile.txt [%d%%]\r'%i,

Demo:

import time

for i in range(100):
    time.sleep(0.1)
    print 'Downloading File FooFile.txt [%d%%]\r'%i,

Python 3

print('Downloading File FooFile.txt [%d%%]\r'%i, end="")

Demo:

import time

for i in range(100):
    time.sleep(0.1)
    print('Downloading File FooFile.txt [%d%%]\r'%i, end="")

PyCharm Debugger Console with Python 3

# On PyCharm Debugger console, \r needs to come before the text.
# Otherwise, the text may not appear at all, or appear inconsistently.
# tested on PyCharm 2019.3, Python 3.6

import time

print('Start.')
for i in range(100):
    time.sleep(0.02)
    print('\rDownloading File FooFile.txt [%d%%]'%i, end="")
print('\nDone.')

Solution 3

Use a terminal-handling library like the curses module:

The curses module provides an interface to the curses library, the de-facto standard for portable advanced terminal handling.

Solution 4

Print the backspace character \b several times, and then overwrite the old number with the new number.

Solution 5

For Python 3xx:

import time
for i in range(10):
    time.sleep(0.2) 
    print ("\r Loading... {}".format(i)+str(i), end="")

View more solutions

Comments

[wim]

you might be interested in this easy-to-use module, it's a text progress bar. pypi.python.org/pypi/progressbar/2.2

[Chris Ballance]

interesting, I hadn't thought of doing it that way.

[ephemient]

Very common and simple solution. Note: if your line is longer than the width of your terminal, this gets ugly.

[scottm]

I also had to add a call to sys.stdout.flush() so the cursor didn't bounce around

[Diego Herranz]

Not available for Windows.

[Nathan Donnellan]

I like this because it doesn't clear previous commands (if you have multiple stages you want to leave on the screen)

[Plexico]

@Diego there's now a support library for curses module on Windows. see stackoverflow.com/a/19851287/1426237

[cod3monk3y]

Using carriage return (e.g. print 'Downloading.... \r') also doesn't clear previous data, but it prevents having to know how far back to back up.

[EarlCrapstone]

Is it possible to do this with multiple lines? Lets say I have three different downloads, and I want to show the progress of each one on its own line.

[hkoosha]

use this for python 3+: print('Downloading File FooFile.txt [%d%%]\r'%i, end="")

[augurar]

I like to put the \r at the beginning of the line, and add a \x1b[K to clear the previous text.

[Ogen]

What if I have multiple lines? For example, multiple downloads happening at the same time. It doesn't seem to work when I just add newlines, it prints infinitely. I.e., sys.stdout.write("Download progress: %d%% \n\r" % (progress) ) doesnt work

[Joshua Grosso Reinstate CMs]

Why is this better than the above (I'm a Python n00b, so please excuse my ignorance :-))?

[PM 2Ring]

In modern Python, you can supply an arg of flush=True to print, so there's no need for the extra sys.stdout.flush() call.

[Cyrus]

It seems like the simplest solution for python 3 (as mentioned in answers below) is: print("sample text", end='\r", flush=True)

[Yul Kang]

On PyCharm Debugger console, \r needs to come before the text. Otherwise, the text may not appear at all, or appear inconsistently. I added the version that works for me as an edit, because I couldn't write multi-line code in this answer. I put it on my gist so people can view it while the edit is awaiting approval: gist.github.com/yulkang/40168c7729a7a7b96d0116d8b1bc26df

[battey]

"\r" at the end of the string works for me in the debugger console on PyCharm 2020.1 (PyCharm 2020.1.2 (Community Edition); Build #PC-201.7846.77, built on May 31, 2020).

[codesnerd]

@Cyrus that worked seamlessly. Just fix the quotes with \r :)

[Dave]

First example has "sys.sdtout" gives a syntax error. Change to "sys.stdout".