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Curl commandline, "retry" issue

From: Philippe HAMEAU <>
Date: Tue, 8 Jan 2008 11:20:49 +0100

Hi all,

I am really thankful to you all for cURL's quality and features. It's
really a powerful and handy tool !

I guess I have found a bug though using latest commandline (win32's)
I have to download old iso's of Debian for some old project, and haven't
been able to find another server than this one (if anyone could help btw,
I'm looking for Debian 3.1r1CD or DVD Isos...).
I'm downloading off a slow connection (512 Kbps DSL line), and I get
disconnected quite often. I dunno if the server is slow or loaded.

I tried the following :
C:\curl-7.17.1>curl -O --retry 10 -y 15 -Y 10240 -C -
  % Total % Received % Xferd Average Speed Time Time Time
                                 Dload Upload Total Spent Left
  0 369M 0 15844 0 0 895 0 5d 00h 0:00:17 5d 00h
Warning: Transient problem: timeout Will retry in 1 seconds. 10 retries
Throwing away 15844 bytes
  0 369M 0 59644 0 0 3282 0 32:46:53 0:00:18 32:46:35
Warning: Transient problem: timeout Will retry in 2 seconds. 9 retries
Throwing away 59644 bytes
  0 369M 0 0 0 0 0 0 --:--:-- 0:00:20 --:--:--
Warning: Transient problem: timeout Will retry in 4 seconds. 8 retries
  0 369M 0 52344 0 0 1822 0 59:03:00 0:00:28 59:02:32
Warning: Transient problem: timeout Will retry in 8 seconds. 7 retries
Throwing away 52344 bytes
  0 369M 0 695k 0 0 12374 0 8:41:41 0:00:57 8:40:44
Warning: Transient problem: timeout Will retry in 16 seconds. 6 retries

First issue : it looks like the amount of data gotten at every try is
"trown away" (= discarded ?). Is it really what happens, or is bad display

Second issue : in the end, the file is broken. I guess it's a problem with
continuing. Maybe some garbage bytes are received when a connection is
about to die. Is there a way to tell the "--continue " directive to
rollback some, let's say, 4K ? It could look like Perl arrays : -C with a
positive value continues at the given offset, and -C with a negative value
(-n) continues n bytes before the current size.

Unfortunately, i'm not a developper myself, and i'm not sure I could help
on this.


Philippe HAMEAU
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Received on 2008-01-08