portscanner.py

import socket
import subprocess
import sys

from datetime import datetime

#Blank your screen
subprocess.call('clear', shell=True)

#Ask for input
remoteServer = input("Enter a remote host to scan: ")
remoteServerIP = socket.gethostbyname(remoteServer)

#Print a nice banner with information on which host we are about to scan
print ("_") * 60
print ("Please wait, scanning remote host"), remoteServerIP
print ("_") *60

#Check the date and time the scan was started
t1 = datetime.now()

#Using the range function to specify ports
#Also we will do error handling

try:
    for port in range (1,5000):
        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    result = sock.connect_ex((remoteServerIP, port))
    if result ==0:
        print ("Port {}:        Open").format(port)
        sock.close()

except KeyboardInterrupt:
    print ("You pressed Ctrl+C")
    sys.exit()

except socket.gaierror:
    print ("Hostname could not be resolved. Exiting")
    sys.exit()

except socket.error:
    print ("Couldn't connect to server")
    sys.exit()

#Checking time again
t2 = datetime.now()

#Calculate the difference in time to now how long the scan took
total = t2 - t1

#Printing the information on the screen
print ("Scanning Completed in in ', total")