7 replies to this topic

[spaceyguy]

I was trying to duplicate the effect of using the Stream.CopyTo, so that I could redirect the output of a HttpWebResponse response stream to a FileStream. I created the following to as an attempt; it works on regular .Net but not on the netduino+.

FileStream fOut = File.Create(@"\SD\downed");
HttpWebRequest req = (HttpWebRequest)WebRequest.Create("http://example.com");//"http://feeds2.feedburner.com/the404/");
HttpWebResponse resp = (HttpWebResponse)req.GetResponse();
Stream respStream = resp.GetResponseStream();
int read = respStream.ReadByte();
while (read != -1)
{
    read = respStream.ReadByte();
    fOut.WriteByte((byte)read);
}

respStream.Close();
fOut.Close();

[Chris Walker]

Hi spaceyguy, What is the result if you try doing that with .NET MF? Chris

[spaceyguy]

I'm trying to download the requested page.

[Chris Walker]

Sorry, let me ask that another way...what error are you getting when you run the code? Is a feature not implemented? Do you get an exception?

[Corey Kosak]

Whatever other issues it may have, it also seems to have a bug, as it unconditionally throws away the first byte read without copying it. You probably want:

while(true) {
  int read = respStream.ReadByte();
  if(read == -1)
     break;
  fOut.WriteByte((byte)read);
}

[spaceyguy]

Thanks Corey, I knew there was a better design but I was having a mental block preventing me to find one.

Chris as for what actually happens, after 5 minutes I get the following:

The thread '<No Name>' (0x2) has exited with code 0 (0x0).
    #### Exception System.Net.Sockets.SocketException - CLR_E_FAIL (1) ####
    #### Message: 
    #### Microsoft.SPOT.Net.SocketNative::recv [IP: 0000] ####
    #### System.Net.Sockets.Socket::Receive [IP: 0018] ####
    #### System.Net.Sockets.NetworkStream::Read [IP: 0062] ####
    #### System.Net.InputNetworkStreamWrapper::RefillInternalBuffer [IP: 0038] ####
    #### System.Net.InputNetworkStreamWrapper::ReadByte [IP: 000e] ####
    #### DownFile.Program::Main [IP: 0026] ####
    #### SocketException ErrorCode = 10060
    #### SocketException ErrorCode = 10060
A first chance exception of type 'System.Net.Sockets.SocketException' occurred in Microsoft.SPOT.Net.dll
    #### SocketException ErrorCode = 10060
An unhandled exception of type 'System.Net.Sockets.SocketException' occurred in Microsoft.SPOT.Net.dll

[Chris Walker]

spaceyguy, It looks like the final ReadByte() is waiting for a timeout of 5 minutes before throwing a timeout exception of sorts. Do you get all of your data before that call? Perhaps the ReadByte() call is improperly timing out instead of just returning EOF? Chris

[spaceyguy]

It only creates the file, nothing is output into it.
EDIT: When I substituted respStream with a FileStream it did work, if that means anything.
EDIT 2: I changed the page that it requested and it was successful.