Python - modules(import statements, sys module, sys.path)

Programming Python
( O'Reilly Media)
Mark Lutz(著)

開発環境

• OS X Mavericks - Apple(OS)
• Emacs (CUI)、BBEdit - Bare Bones Software, Inc. (GUI) (Text Editor)
• Python 3.4 (プログラミング言語)

Head First C ―頭とからだで覚えるCの基本(David Griffiths (著)、Dawn Griffiths (著) 中田 秀基(監訳)(翻訳)、木下 哲也 (翻訳)、オライリージャパン)の8章(スタティックライブラリとダイナミックライブラリ: ホットスワップ可能なコード)、makeマグネット(p.361)をpythonで考えてみる。

makeマグネット(p.361)

コード(BBEdit, Emacs)

hfsecurity.py

#!/usr/bin/env python3
#-*- coding: utf-8 -*-

def encrypt(b):
    for i in range(len(b)):
        b[i] = b[i] ^ 31

def checksum(s):
    c = 0
    b = s.encode('utf-8')
    for n in b:
        c += c ^ n
    return c

bank_vault.py

#!/usr/bin/env python3
#-*- coding: utf-8 -*-

import hfsecurity
import sys

for path in sys.path:
    print(path)

s = 'Speak friend and enter'
b = bytearray(s.encode('utf-8'))

hfsecurity.encrypt(b)
s = bytes(b).decode('utf-8')
print('{0}に暗号化しました。'.format(s))
print('チェックサムは{0}です。'.format(hfsecurity.checksum(s)))
b = bytearray(s.encode('utf-8'))
hfsecurity.encrypt(b)
s = bytes(b).decode('utf-8')
print('{0}に復号化しました。'.format(s))
print('チェックサムは{0}です。'.format(hfsecurity.checksum(s)))

入出力結果(Terminal, IPython)

$ ./bank_vault.py
/Users/kamimura/Documents/py/hfc/ch8/hfsecurity
/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/Scrapy-0.22.2-py3.4.egg
/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/cssselect-0.9.1-py3.4.egg
/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/pyOpenSSL-0.14-py3.4.egg
/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/lxml-3.3.5-py3.4-macosx-10.9-x86_64.egg
/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/queuelib-1.1.1-py3.4.egg
/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/w3lib-1.5-py3.4.egg
/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/Twisted-14.0.0-py3.4.egg
/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python34.zip
/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4
/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/plat-darwin
/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/readline
/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/lib-dynload
/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages
/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/PyObjC
Loz~t?ymvzq{?~q{?zqkzmに暗号化しました。
チェックサムは89561741です。
Speak friend and enterに復号化しました。
チェックサムは89548156です。
$