Re: Ftp freezes on w32

[Lennart Borgman <lennart.borgman.073@student.lu.se>]

Lennart Borgman wrote:
> I have seen a problem with ftp on w32 which I have not had time to 
> report before. The problem is that if I make a small pause for some 
> minutes then ftp hangs. Looks like there perhaps is some problem with 
> the ftp process. Here is a more detailed description:
>
>
> I have downloaded the ftp program mentioned on 
> http://www.emacswiki.org/cgi-bin/wiki/AngeFtp and my 
> ange-ftp-ftp-program-name is c:/dl/ftp-for-win32/Release/ftp.exe. I am 
> using w2k on this pc. My CVS Emacs is from 2006-11-03.
>
> I open a remote file with the name 
> "/ftp:someuser@ftp.somehost.com:/htdocs/somepath/index.html". After 
> doing the first changes to the remote file point is on line 79 in the 
> buffer "*ftp someuser@ftp.somehost.com*".
>
> Now I wait maybe 10 min. Then I try again to change the file. Now 
> Emacs freezes right after the first character, but C-g helps and the 
> screen gets updated again. Looking in the ftp buffer point is still on 
> line 79 right after the prompt. However now there is some text after 
> the prompt:
>
>  ftp> quote mdtm /htdocs/somepath/index.html
>
> If I in the window showing the ftp buffer now press up arrow I get the 
> error message:
>
>  Wrong type argument: processp, nil

I have looked at this a bit more. The process get killed in 
`ange-ftp-wait-not-busy' so there is no strange with that the process is 
gone.

However what is happening is that the `ange-ftp-wait-not-busy' never 
ends. The process filter in `ange-ftp-process-filter' recieves a string 
with only nulls (in the argument str).

Since this is reproducible it seems possible to make a fix for it. A 
signal can be sent from the process filter and this can be caught in 
`ange-ftp-raw-send'. But it does not seem quite right to me.

Is there not something suspicious about that the process filter receives 
just nulls? Is there something wrong with emacs_read?