Another Script Variable Question

[Ruler2112]

I'm having a problem reading variables with the read command from within a script. This script is being fired from xinetd in response to connections being made on a specific port number. In the script, I have the following:

echo "U"
read username
echo "-$username-" > /dev/tty2

echo "P"
read password
echo "-$password-" > /dev/tty2

echo "M"
read machinename
echo "-$machinename- > /dev/tty2

I have the second echo in there to see exactly what is in the variables. Now I can write over the network from windoze in a program written in C++ using something such as this:

char datatoSend[256];
//Read in variable via dialog box
proxyData[strlen(datatoSend)] = '\n';
proxyData[strlen(datatoSend) + 1] = '\0';
WriteExact(datatoSend, strlen(datatoSend));

//WriteExact (not written by me) snippet
//Does the socket locking here
while (i < bytes) {
  j = send(m_sock, buf+i, bytes-i, 0);
  //Error checking here
  i+=j;
  }

Writing from windoze to the script works perfectly doing this. However, if I telnet from another linux box or from windoze on this port, the variables are read, but the end is screwed up. The first hypen will echo, then the contents of the variable, but the cursor will reset to the beginning of that line before the second hyphen echos. I'm hypothesizing that some unprintable character is embedded in the variable. Why this doesn't happen from windoze is beyond me, but I would very much like it to work with both. (At least from a C++ app on win and from a shell on linux.) Is there a command to strip out all unprintable characters from within a variable?

[SpookyEddy]

Sounds like your variable has a trailing newline (\n) or something similar.

Unless you have a really good reason for using a shell script I would strongly suggest looking at a more powerful language such as Ruby, Python or Perl.

Is the shell script actually reading in from a socket?

What exactly are you attempting to achieve with the script?

Thanks

ed

[Ruler2112]

That's exactly what I was thinking Eddy, but have no way to prove or disprove that theory, nor do I know of a way to strip out all the unprintable characters from a variable.

What I'm trying to do is make a script to act as a proxy server for an application. Read in the username and password in response to prompts (so the application knows what to send at what time), then the machine name. The script then executes a command (netcat) to redirect all the traffic coming in to the appropriate machine on the network. This way, I need a single port open on the firewall coming into a linux box instead of one for each machine that needs to be accessed. (A *lot* more secure and considerably less expensive.)

I have xinetd set up to listen on a specific port (the one that is going to be forwarded through the firewall of our ISP) and set to execute the script when a connection is made. I don't know if this answers your question if the script is reading from a socket or not. (I've not ever done anything like this before.)