Let us create a few try-except code blocks and put one potential error type in each block. In order to get a user input, the argparse module can be used. This module is more powerful than simply parsing command-line arguments using sys.argv. In the try-except blocks, put typical socket operations, for example, create a socket object, connect to a server, send data, and wait for a reply.

The following recipe illustrates the concepts in a few lines of code.

Listing 1.7 shows socket_errors as follows:

#!/usr/bin/env python 
# Python Network Programming Cookbook, Second Edition -- Chapter - 1 
# This program is optimized for Python 2.7.12 and Python 3.5.2. 
# It may run on any other version with/without modifications. 
 
import sys 
import socket 
import argparse  
 
 
def main(): 
    # setup argument parsing 
    parser = argparse.ArgumentParser(description='Socket Error Examples') 
    parser.add_argument('--host', action="store", dest="host",
                                                        required=False) 
    parser.add_argument('--port', action="store", dest="port", type=int,
                                                        required=False) 
    parser.add_argument('--file', action="store", dest="file",
                                                        required=False) 
    given_args = parser.parse_args() 
    host = given_args.host 
    port = given_args.port 
    filename = given_args.file 
     
    # First try-except block -- create socket  
    try: 
        s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) 
    except socket.error as e: 
        print ("Error creating socket: %s" % e) 
        sys.exit(1) 
     
    # Second try-except block -- connect to given host/port 
    try: 
        s.connect((host, port)) 
    except socket.gaierror as e: 
        print ("Address-related error connecting to 
                server: %s" % e) 
        sys.exit(1) 
    except socket.error as e: 
        print ("Connection error: %s" % e) 
        sys.exit(1) 
     
    # Third try-except block -- sending data 
    try: 
        msg = "GET %s HTTP/1.0

" % filename 
        s.sendall(msg.encode('utf-8')) 
    except socket.error as e: 
        print ("Error sending data: %s" % e) 
        sys.exit(1) 
     
    while 1: 
        # Fourth tr-except block -- waiting
           to receive 
          data from remote host 
        try: 
            buf = s.recv(2048) 
        except socket.error as e: 
            print ("Error receiving data: %s" % e) 
            sys.exit(1) 
        if not len(buf): 
            break 
        # write the received data 
        sys.stdout.write(buf.decode('utf-8'))  
     
if __name__ == '__main__': 
    main()