OpenEuphoria

2. Re: Problem with FTP

• Posted by mattlewis (admin) Jan 08, 2010
• 1656 views

Could you elaborate a little on this? Does this mean using the v4 std library?

Matt

4. Re: Problem with FTP

• Posted by SergioGelli Jan 08, 2010
• 1638 views

Hi Matt and Michael

I am using "eunet.e" and "FTP stub" examples and V3.1.1.

The problem occurs when a line (as below) is executed and the connection to the Internt is very slow or dropped for some reason that does not matter here

eucode

status = eunet_send12(socketT,"NOOP "&13&10,0)

data = eunet_recv12(socketT,0)

end eucode

This is just one example, but the problem also occurs in all other commands (PASS, RETR, STOR and others)

The problem I have is that the program stops responding while waiting for response from the FTP, so I can not do any work on this program's window until it comes to server response (which eventually takes a long time)

6. Re: Problem with FTP

• Posted by sergelli Jan 11, 2010
• 1505 views

o.k The "eunet_recvfrom (socketR, MSG_DONTWAIT)" works well. However, it is not very different from the "eunet_recv (socketR, 0)" In both cases, I can not do anything until the file is downloaded I want a function to stop receiving a file (or do anything else) without closing the program

Currently, the ways to stop the collection are: 1-Close the program 2-Burning PID 3-Wait Internet fall 4-Turn Off Computer

So, I still unresolved for my problem.

8. Re: Problem with FTP

• Posted by m_sabal Jan 12, 2010
• 1458 views

The default block size is 4K. This means, in order to receive a file larger than 4K, you have to be using a loop. If this is a command-line program, use get_key to check for a keyboard interrupt. If using win32lib, check the documentation for doEvents() and add a global flag that can be used to terminate the loop early. I'm afraid I can't help with wxWindows, but I'm sure there's a similar way to check or process the event queue from inside a loop. If you are trying to interrupt a file transfer of 4K or less, you will have to modify the BLOCK_SIZE constant in eunet.e to a smaller value.

10. Re: Problem with FTP

• Posted by jimcbrown (admin) Jan 12, 2010
• 1417 views

I am confused as to what the problem is. Your wording suggests that you want toe FTP download to be aborted whenever you use the program to do anything else, which seems nonsensical to me.

I'm going to assume that

a) the FTP connection dropping continues to hang your GUI

b) the FTP download is not being aborted when the FTP connection fails

I think you need to do the following:

a) use eunet_recvfrom() with MSG_DONTWAIT

b) change the BLOCK_SIZE from 4K to a much smaller value

c) chuck out your while loop. if you are simply looping using eunet_recv() or eunet_recvfrom() until you've got the entire file, even if the socket is not blocking, the while loop will block your program until its finished. You need to rewrite this so that the data is only recv'd on an event call

Alternatively, you can stop using eunet for FTP and instead just use this:

system("start /b ftp "&ftp_url_to_download&", 2) 

12. Re: Problem with FTP

• Posted by jimcbrown (admin) Jan 12, 2010
• 1441 views

That was not step three. It was an alternative to all three steps, and an alternative to using eunet.

Anyways, I do not understand why it has hung your GUI. start /b is *suppose* to run the command in the background - and return immediately to the calling program. So what is suppose to happen is that system() calls start, start runs ftp in the background, ftp.exe starts downloading the file while your program continues to operate (GUI fully functional and responsive).

Ok, so then you do have both problems as I describe below:

a) the FTP connection dropping *or being slow* continues to hang your GUI b) the FTP download is not being aborted when the FTP connection fails

So it seems the problem is with step 3, then....

14. Re: Problem with FTP

• Posted by jimcbrown (admin) Jan 12, 2010
• 1394 views

No, not directly. If you know the size of the file being downloaded though then you can simply do a dir() on the file to find out if it is done yet or not.

Otherwise, the following batch script provides a work-around:

@echo off 
rem Lets assume this batch script is named ftpbatch.bat 
rem Usage: ftpbatch.bat ftp://site.tld/file/to/get c:\temp\ok_download_is_done.txt 
ftp "%1" 
echo %ERRORLEVEL% > "%2" 

and then you would do

system("start /b ftpbatch.bat "&ftp_url_to_download&" "&completion_file, 2) 

Then you could do a dir() on completion_file, and when it is created you know the ftp download is finished. (And if you need to see the exit code of ftp.exe to know if the download was successful or aborted, you can read the exit code in the file.)

16. Re: Problem with FTP

• Posted by m_sabal Jan 13, 2010
• 1382 views

In order to run any socket-based routine as a background operation, you need to have true threading. Euphoria does not currently support true threading (which with today's multi-core CPUs, isn't the best way to code anymore anyway), so the only way to do a parallel process is to spawn a separate program. Jim's suggestion is one way to do that, and is probably the simplest way of accomplishing your goals. This is one reason a full FTP implementation hasn't been included in eunet yet.

If you wanted a pure Euphoria solution, you could have your ftp routines built as a separate program, probably as a Windows service, and include either a file-based or socket-based inter-process communication API to allow your GUI to give instructions to the FTP process and query its status. Obviously that is a bit more complicated, but parallel programming usually is.

18. Re: Problem with FTP

• Posted by SergioGelli Jan 14, 2010
• 1382 views

I think a small program Euphoria, using "eunet.e", for example, STOR.EXE, could be executed within the main program with "system("stor.exe parameter 1 parameter 2 parameter 3 ...", 2)" , this is like the suggestion made by JimcBrown.

This operation would be in the background, o.k.?

Meanwhile, the main program could monitor the completion of tasks and enable the User to choose an abortion, if it happens one undesired event.

But I do not know how to kill the execution of STOR.EXE, how can I do that? Does this will work?

20. Re: Problem with FTP

• Posted by jimcbrown (admin) Jan 14, 2010
• 1402 views

Huh? What analysis? Are you saying that pre-emptive multithreading is less useful than being able to take advantage of multi-core? Or are you saying that true multiprocess parallel programs are becoming more important these days?

Cool. I'm impressed.