hasan-kamal / Telnet-Client

A telnet client implementation in C

Telnet-Client

Introduction

• This is an implementation of a telnet client in C
• Client is implemented using IO multiplexing (see select() system call)

Repository structure

• src/ contains the source code
  • src/telnet_client.c contains the telnet client implementation
• compile.sh bash shell-script can be used to compile the client from source

Build

• First compile by cd-ing into the root of this repository and then running command ./compile.sh
• Run ./bin/telnet_client.out <ip_address> <port_no> to start the telnet client and connect to telnet server at IP address ip_address, port number port_no

Example Runs

• Using the following sample commands, you can connect to some interesting open servers and see the client in action
  • ./bin/telnet_client.out towel.blinkenlights.nl 23 (Star Wars asciimation)
  • ./bin/telnet_client.out india.colorado.edu 13 (get the time)

    Hasans-MacBook-Pro:Telnet-Client hasankamal$ ./bin/telnet_client.out india.colorado.edu 13
    connected successfully!
    
    58680 19-07-16 13:24:15 50 0 0 442.0 UTC(NIST) * 
    EOF reached, connection closed?
    Hasans-MacBook-Pro:Telnet-Client hasankamal$

References

1. Unix Socket API
2. Telnet protocol specification
3. IO multiplexing using select() system call