how to accomplish dl progress bars?

[flamesrock]

Certain web applications, everything from wget to downloader for X has
this nifty feature I'd like to accomplish in python.

Its the progress bar/time elapsed/time remaining scheme

Filename | Progress | Speed (kB/s) | T/Elapsed | T/Remaining
----------------------------------------------------------------------------
blah.bin |------>45% | 56.6 | 02:39 | 02:45
file2.bz2 |--->33% | 35.0 | 05:22 | 11:24
etc |-------->60% | 47.5 | 00:14 | 00:08

(could be either text or a gui..)

So where would one begin to accomplish this sort of thing efficiently?

I've searched the web and there are plenty of resources on network
programming in python, but how could I
1) keep track of download speed
2) calculate t/elapsed/remaining
3) output that to a progress bar

w/o spawning countless threads to do the many calculations and avoid
eating up the entire CPU.

This seems like it would require a lot of resources and easily go out
of sync with the real world file transfer. To compound problems, I have
a very limited understanding of threads and using multiple threads that
rely on eachother doesn't make very much sense.

Can anyone point me in the right direction?

-thanks in advance

[Edvard Majakari]

"flamesrock" <fl********@gmail.com> writes:

Certain web applications, everything from wget to downloader for X has
this nifty feature I'd like to accomplish in python.

Its the progress bar/time elapsed/time remaining scheme

Filename | Progress | Speed (kB/s) | T/Elapsed | T/Remaining
----------------------------------------------------------------------------
blah.bin |------>45% | 56.6 | 02:39 | 02:45
file2.bz2 |--->33% | 35.0 | 05:22 | 11:24
etc |-------->60% | 47.5 | 00:14 | 00:08

See python cookbook. The idea is simply to print out stuff and when updating,
erase previous characters eg. using '\r' ASCII code. Python Cookbook has a
progress bar implementation, you could use that as a basis for your code
(speed, t/elapsed and t/remaining are technically no different; if you can do
a progress bar, you can do those others as well).

--
# Edvard Majakari Software Engineer
# PGP PUBLIC KEY available Soli Deo Gloria!

$_ = '456476617264204d616a616b6172692c20612043687269737 469616e20'; print
join('',map{chr hex}(split/(\w{2})/)),uc substr(crypt(60281449,'es'),2,4),"\n";

[flamesrock]

thanks! I didn't realize it was in the cookbook:

http://aspn.activestate.com/ASPN/Coo.../Recipe/168639