The last time I answered this question, it was for a COBOL application running an HP3000 Image database application, but the principle for a pre-forking server is the same. Here was my response.

My approach is this

Have the application start, and open a listen socket

The application forks to create N children. They thus inherit the listening socket.

The children run like this: 

     initialize--open files, databases
     send message to parent that we initialized correctly
     while (1) {
       (optional) inform parent we are available
       accept on listen sock
       (optional) inform parent we are busy
       read data
       process transaction
       send response
    }

[download]
The parent just monitors the children for unexpected death. It can start a new server if one dies or if the number of available servers falls below some threshold.

There are a few little details, like how to shut down, making sure you don't get into a loop of restarting a crashing server, etc.

Your initialization would consist of opening the Telnet connection. The "process transaction" would consist of sending the query to the process's open Telnet session, getting the response and sending data back to the connection.

In reply to Re: Passing client information between multiple sockets... by Thelonius
in thread Passing client information between multiple sockets... by rlb3

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