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Trap KeyboardInterrupt and EOFError for graceful program termination (Python recipe) by Vasudev Ram
ActiveState Code (http://code.activestate.com/recipes/580718/)

This recipe shows how to trap the KeyboardInterrupt and EOFError Python exceptions so that they do not crash your program. As a vehicle to show this, it uses a small Python utility that shows the ASCII code for any ASCII character you type.

Python, 32 lines
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from __future__ import print_function
"""
char_to_ascii_code.py
Purpose: Show ASCII code for a given character, interactively, 
in a loop. Show trapping of KeyboardInterrupt and EOFError exceptions.
Author: Vasudev Ram
Web site: https://vasudevram.github.io
Blog: https://jugad2.blogspot.com
Product store: https://gumroad.com/vasudevram
"""

print("This program shows the ASCII code for any given ASCII character.")
print("Exit the program by pressing Ctrl-C or Ctrl-Z.")
print()

while True:
    try:
        c = raw_input( \
        "Enter an ASCII character to see its ASCII code: ")
        if len(c) != 1:
            print("Error: need a string of length 1; retry.")
            continue
        print("Character:", c)
        print("Code:", ord(c))
    except KeyboardInterrupt as ki:
        print("Caught:", repr(ki))
        print("Exiting.")
        break
    except EOFError as eofe:
        print("Caught:", repr(eofe))
        print("Exiting.")
        break

Without the handling of these two exceptions, KeyboardInterrupt and EOFError, pressing either Ctrl-C or Ctrl-Z (latter followed by Enter) will abnormally terminate the program with one of those exceptions respectively. The handlers ensure that the program terminates without crashing and without giving a stack trace.

Tags: ascii, error, exception, handler, shutdown, terminate, utilities, utility