multiple inetget with $INET_DOWNLOADBACKGROUND

[rudi]

Hello,

 

from some version archive for a free software I wrote a script to downloads all these versions and ist doing a resort / rename of the resulting files. As it's about 200 files, I wanted to use the background parameter of InetGet(), but experienced, that it doesn't seem to work.

 

The help file tells:

If the background parameter is set to $INET_DOWNLOADBACKGROUND (1) the function returns immediately and the download continues in the background. The function InetGetInfo() can be used to check the status of the download. It takes the handle returned from InetGet().

Multiple downloads are supported if they are started in background mode.
 

Q1: Is there a limit for the number of the simultaneous downloads, that can run at the same time? (Number of Windows' sockets e.g.)

Q2: Propably I have to monitor the background downloads and keep the script running, until they are all done, and when I don't do that, the "natural end" of the script (while background downloads are still running) will terminate the running downloads as well? (

 

The help file examle uses a loop:

; [snip]
Do
    Sleep(250)
Until InetGetInfo($hDownload, $INET_DOWNLOADCOMPLETE)

 

 

 

 

Edited February 2 by rudi

[argumentum]

1 hour ago, rudi said:

Q1: ...
Q2: ...

..well, ..give it a try. 
I would every so often check that  InetGetInfo($hDownload1ofX, $INET_DOWNLOADCOMPLETE)   a check, say, every 10 sec ?, to know when to close the script.

[Nine]

I have seen a true reduction of performance using this kind of approach while you are having lots of downloads at a time :

 

But it seems to get much more effective using a multi-threading approach :

 

ps.  AutoIt is and will stay single threaded, no matter how hard you try, multi-threaded will always be more effective under the right circumstances.

Edited February 2 by Nine

[rudi]

@Nine: Thanks for pointing out your Multi-Threading UDF

 

Anybody experienced regarding the Windows' limit for concurrent downloads, in combination with doing the downloads from an Autoit Script?

 

 

Mentioned e.g. here:  https://stackoverflow.com/questions/38511515/how-to-increase-the-number-of-concurrent-downloads-initiated-by-an-extension

[SOLVE-SMART]

Hi @rudi 👋 ,

maybe you could consider to avoid InetGet() at all and use "_WinHttpSimpleRequest" or a similar request of this UDF (library).

#include "WinHttp.au3"

In the "au3WebDriver" project we (@Danp2, @milpok (also me kind of)) also discovery InetGet() is not the robustess way of downloading files.
I personally use cURL (curl.exe) for such things which is very handy 😀 .

Best regards
Sven

[Nine]

@rudi  Yep, this is exactly what I observed when downloading from a single thread.  Only a few gets started the rest waiting in line...

[rudi]

OK, thanks for the Input.

So I think I will use Autoit to create the wanted folder structure and to create a powershell script doing the downloads, always e.g. 10 simultaneously, using Invoke-WebRequest