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Bash Shell启动方式与rc脚本

Shell的不同分类

根据启动Bash Shell的方式不同，对Shell有两种分类方式

登录Shell与非登录Shell

根据Shell的启动方式不同，可以将Shell分为

This is a brief introduction about how Linux kernel handles the send system call.

This study is based on kernel version 3.7.2, which is the latest stable kernel when writing this study.

How system call is defined

In the latest kernel, the system call is defined using the SYSCALL_DEFINEx macro, in which x is the number of arguments. For example, in order to find the definition of asmlinkage long sys_sendto(int, void __user *, size_t, unsigned, struct sockaddr __user *, int);, you need to grep for SYSCALL_DEFINE6 because it has 6 arguments.

The definition of the system call send can be found at net/socket.c.

	class API(app.page):
	pass


	class DjangoAPI(API):
	model = None

	def __init__(self):
	self.qs = self.model.objects
	self.exclude = []

	from itertools import product
	import string

	print(list(product(string.lowercase[:13],repeat=2)))

	[('a', 'a'), ('a', 'b'), ('a', 'c'), ('a', 'd'), ('a', 'e'), ('a', 'f'), ('a', 'g'), ('a', 'h'), ('a', 'i'), ('a', 'j'), ('a', 'k'), ('a', 'l'), ('a', 'm'), ('b', 'a'), ('b', 'b'), ('b', 'c'), ('b', 'd'), ('b', 'e'), ('b', 'f'), ('b', 'g'), ('b', 'h'), ('b', 'i'), ('b', 'j'), ('b', 'k'), ('b', 'l'), ('b', 'm'), ('c', 'a'), ('c', 'b'), ('c', 'c'), ('c', 'd'), ('c', 'e'), ('c', 'f'), ('c', 'g'), ('c', 'h'), ('c', 'i'), ('c', 'j'), ('c', 'k'), ('c', 'l'), ('c', 'm'), ('d', 'a'), ('d', 'b'), ('d', 'c'), ('d', 'd'), ('d', 'e'), ('d', 'f'), ('d', 'g'), ('d', 'h'), ('d', 'i'), ('d', 'j'), ('d', 'k'), ('d', 'l'), ('d', 'm'), ('e', 'a'), ('e', 'b'), ('e', 'c'), ('e', 'd'), ('e', 'e'), ('e', 'f'), ('e', 'g'), ('e', 'h'), ('e', 'i'), ('e', 'j'), ('e', 'k'), ('e', 'l'), ('e', 'm'), ('f', 'a'), ('f', 'b'), ('f', 'c'), ('f', 'd'), ('f', 'e'), ('f', 'f'), ('f', 'g'), ('f', 'h'), ('f', 'i'), ('f', 'j'), ('f', 'k'), ('f', 'l'),

	#!/bin/bash

	# FAIL!
	echo a\| read i
	echo $i

	# WORKS

	read i <<<$(echo a)
	echo $i

	def get_readonly_fields(self, request, obj=None):
	if obj and obj.is_processed:
	return ('csv_file',) + self.readonly_fields
	else:
	return self.readonly_fields

	#!/usr/bin/env python
	# vim: set fileencoding=utf-8 ts=4 sw=4 tw=79 :

	from __future__ import (unicode_literals, absolute_import,
	division, print_function)

	import requests
	from lxml import etree
	from io import StringIO

	import os
	from google.appengine.ext import vendor

	"""
	1. Create a virtualenv directory at the root of your project, name it "venv"
	2. Install packages needed in your project
	3. Freeze it and save the package list into requirements.txt file, add it to
	version control
	4. Exclude "venv" directory from version control
	5. Save the content of this file as "appengine_config.py", and put it at the

	from __future__ import absolute_import
	from __future__ import division
	from __future__ import print_function
	from __future__ import unicode_literals

	class MyList(list):
	def __init__(self, raw_list, start=None, stop=None):
	self.raw_list = raw_list
	self.start = start or 0
	self.stop = stop or len(raw_list)-1