HTTP request & HTTP protocol violation

[Henrik]

Hi,

I am trying to read some industrial webservers using the HTTP/CGI webequest
like this:

wrs = (HttpWebRequest)WebRequest.Create(HTTP/CGI-string);
mwst = (HttpWebResponse wrs.GetResponse();
str = mwst.GetResponseStream();

This usually works fine but on some servers i get:
"System.Net.WebException: The underlying connection was closed: The server
committed an HTTP protocol violation."

The same request works fine in IE and basically i just want whatever comes
from the server to parse it...

So how can i get around this http protocol violation and stille get the data
from the server ? - Is there some alternative (- and less sensitive) way to
do a CGi request ?

--
Henrik Hansen

[John Timney \(ASP.NET MVP\)]

When you say it works from a browser - are you doing a post or a get
request. Try forcing a post request through and see if that works from the
net code.

Also, I assume that this (HTTP/CGI-string) is a quoted address string as its
not in your example.
--
Regards

John Timney
ASP.NET MVP
Microsoft Regional Director

"Henrik" <He****@discussions.microsoft.com> wrote in message
news:62**********************************@microsof t.com...

Hi,

I am trying to read some industrial webservers using the HTTP/CGI webequest like this:

wrs = (HttpWebRequest)WebRequest.Create(HTTP/CGI-string);
mwst = (HttpWebResponse wrs.GetResponse();
str = mwst.GetResponseStream();

This usually works fine but on some servers i get:
"System.Net.WebException: The underlying connection was closed: The server
committed an HTTP protocol violation."

The same request works fine in IE and basically i just want whatever comes
from the server to parse it...

So how can i get around this http protocol violation and stille get the data from the server ? - Is there some alternative (- and less sensitive) way to do a CGi request ?

--
Henrik Hansen

[Henrik]

The http request is a string like "http://IP/cgi/command.cgi?blablabla" and
as said it works fine in a browser...

When i add the POST method i just get this:
System.Net.WebException: The operation has timed-out.

/henrik

"John Timney (ASP.NET MVP)" wrote:

When you say it works from a browser - are you doing a post or a get
request. Try forcing a post request through and see if that works from the
net code.

Also, I assume that this (HTTP/CGI-string) is a quoted address string as its
not in your example.
--
Regards

John Timney
ASP.NET MVP
Microsoft Regional Director

"Henrik" <He****@discussions.microsoft.com> wrote in message
news:62**********************************@microsof t.com...

Hi,

I am trying to read some industrial webservers using the HTTP/CGI

webequest

like this:

wrs = (HttpWebRequest)WebRequest.Create(HTTP/CGI-string);
mwst = (HttpWebResponse wrs.GetResponse();
str = mwst.GetResponseStream();

This usually works fine but on some servers i get:
"System.Net.WebException: The underlying connection was closed: The server
committed an HTTP protocol violation."

The same request works fine in IE and basically i just want whatever comes
from the server to parse it...

So how can i get around this http protocol violation and stille get the

data

from the server ? - Is there some alternative (- and less sensitive) way

to

do a CGi request ?

--
Henrik Hansen

[Nicholas Paldino [.NET/C# MVP]]

Henrik,

Are there cookies perhaps on the browser that are being passed to the
server? Also, does the server do anything based on the user agent string
that is sent to the server? Do you have to set up a proxy for the browser
(which would indicate you have to set up a proxy for the WebRequest as
well)?

The server can do a number of things, based on a number of different
parameters other than just the URL string.

Hope this helps.
--
- Nicholas Paldino [.NET/C# MVP]
- mv*@spam.guard.caspershouse.com
"Henrik" <He****@discussions.microsoft.com> wrote in message
news:A6**********************************@microsof t.com...

The http request is a string like "http://IP/cgi/command.cgi?blablabla"
and
as said it works fine in a browser...

When i add the POST method i just get this:
System.Net.WebException: The operation has timed-out.

/henrik

"John Timney (ASP.NET MVP)" wrote:

When you say it works from a browser - are you doing a post or a get
request. Try forcing a post request through and see if that works from
the
net code.

Also, I assume that this (HTTP/CGI-string) is a quoted address string as
its
not in your example.
--
Regards

John Timney
ASP.NET MVP
Microsoft Regional Director

"Henrik" <He****@discussions.microsoft.com> wrote in message
news:62**********************************@microsof t.com...

> Hi,
>
> I am trying to read some industrial webservers using the HTTP/CGI

webequest

> like this:
>
> wrs = (HttpWebRequest)WebRequest.Create(HTTP/CGI-string);
> mwst = (HttpWebResponse wrs.GetResponse();
> str = mwst.GetResponseStream();
>
> This usually works fine but on some servers i get:
> "System.Net.WebException: The underlying connection was closed: The
> server
> committed an HTTP protocol violation."
>
> The same request works fine in IE and basically i just want whatever
> comes
> from the server to parse it...
>
> So how can i get around this http protocol violation and stille get the

data

> from the server ? - Is there some alternative (- and less sensitive)
> way

to

> do a CGi request ?
>
> --
> Henrik Hansen

[Henrik]

Since it is a GET requset i want, i belive this was a wrong track....
/henrik

"Joerg Jooss" wrote:

Henrik wrote:

The http request is a string like
"http://IP/cgi/command.cgi?blablabla" and as said it works fine in a
browser...

When i add the POST method i just get this:
System.Net.WebException: The operation has timed-out.

You cannot just simply change the method to POST. Posting requires data
being written to the request stream. If not, the operation will time out, as
you've seen.
Cheers,

--
Joerg Jooss
www.joergjooss.de
ne**@joergjooss.de

[Henrik]

Hi Nicholas,

We do not use any proxy servers and i can get other information from the
same device using other http requests (Also from .NET/C#). And i dont believe
that any coockies is involved. I have tried to monitor the TCP flow using the
MS Network monitor and nothing seems to be differentin the TCP flow except
from the fact that the .NET http request simply stops due to the violation
error.

So still i believe that the .NET request is too sensitive and i "just" want
a way to collect the raw stream from the device...

/henrik

"Nicholas Paldino [.NET/C# MVP]" wrote:

Henrik,

Are there cookies perhaps on the browser that are being passed to the
server? Also, does the server do anything based on the user agent string
that is sent to the server? Do you have to set up a proxy for the browser
(which would indicate you have to set up a proxy for the WebRequest as
well)?

The server can do a number of things, based on a number of different
parameters other than just the URL string.

Hope this helps.
--
- Nicholas Paldino [.NET/C# MVP]
- mv*@spam.guard.caspershouse.com
"Henrik" <He****@discussions.microsoft.com> wrote in message
news:A6**********************************@microsof t.com...

The http request is a string like "http://IP/cgi/command.cgi?blablabla"
and
as said it works fine in a browser...

When i add the POST method i just get this:
System.Net.WebException: The operation has timed-out.

/henrik

"John Timney (ASP.NET MVP)" wrote:

When you say it works from a browser - are you doing a post or a get
request. Try forcing a post request through and see if that works from
the
net code.

Also, I assume that this (HTTP/CGI-string) is a quoted address string as
its
not in your example.
--
Regards

John Timney
ASP.NET MVP
Microsoft Regional Director

"Henrik" <He****@discussions.microsoft.com> wrote in message
news:62**********************************@microsof t.com...
> Hi,
>
> I am trying to read some industrial webservers using the HTTP/CGI
webequest
> like this:
>
> wrs = (HttpWebRequest)WebRequest.Create(HTTP/CGI-string);
> mwst = (HttpWebResponse wrs.GetResponse();
> str = mwst.GetResponseStream();
>
> This usually works fine but on some servers i get:
> "System.Net.WebException: The underlying connection was closed: The
> server
> committed an HTTP protocol violation."
>
> The same request works fine in IE and basically i just want whatever
> comes
> from the server to parse it...
>
> So how can i get around this http protocol violation and stille get the
data
> from the server ? - Is there some alternative (- and less sensitive)
> way
to
> do a CGi request ?
>
> --
> Henrik Hansen