Python多进程编程及多进程间的通信，数据传输

Python多进程编程及多进程间的通信

多进程编程及进程间的通信

意义：充分利用计算机的资源提高程序的运算速率
定义：通过应用程序利用计算机多个核心达到同时执行多个任务的目的，以此提高计算机的运行速率
实施方案：多进程多线程
并行：计算机同时处理多个任务
并发：同时处理多个任务，内核在不断的任务间小虎切换，达到好像还都在处理运行的效果，但是实际是一个时间点内核只能处理其中一个任务

多进程的优缺点

优点
- 可以使用计算机多核，进行任务的并发执行，提高执行效率
- 空间独立，数据安全
- 运行不受其他进程影响，创建方便
缺点
- 进程的删除和创建消耗的系统资源多

进程（process）

查看进程：ps -aux 查看进程树：pstree 查看父进程：ps -ajx

标志	名称	说明
S	等待态	可中断等待
D	等待态	不可中断等待
T	等待态	暂停状态
R	运行态	包含就绪状态
Z	僵尸进程
<		高优先级
N		优先级较低
l		有子进程的
s		会话组组长
+		前台进程

三态

就绪态：进程具备执行条件，等待系统分配资源
运行态：进程占有CPU，处于运行状态
等待态：进程暂时不具备执行条件，阻塞等待，满足条件后再执行

五态（三态的基础上增加了新建态和终止态）

新建态：创建一个新的进程，获取资源的过程
终止态：进程执行结束，资源释放回收的过程

进程优先级

作用：决定了一个进程的执行权限
动态查看系统中的进程信息：top,用< , >翻页
- 取值范围：-20 — 19 -20优先级最高
使用指定的优先级运行程序
- nice : 指定运行的优先级
  
  e.g. :nice -9 ./while.py —>>以优先级-9运行

进程特征

进程之间运行互不影响，各自独立运行
进程是操作系统资源分配的最小单位
每个进程空间独立，各自占有一定的虚拟内存

孤儿进程

父进程先于子进程退出，此时子进程就称为孤儿进程
孤儿进程会被操作系统指定的进程收养，系统进程就成为了孤儿进程的父进程

僵尸进程

子进程先于父进程退出，但是父进程没有处理子进程的退出状态，此时子进程就会成为僵尸进程
僵尸进程会存留少量的PCB信息在内存中，大量的僵尸进程会消耗系统资源，应该避免僵尸进程的产生

如何避免僵尸进程的产生
- 处理子进程的退出状态
```
pid, status = os.wait()
```
  功能：在父进程中堵塞等待子进程退出
  
  返回值：

要求理解

什么是进程？
了解进程特征
清楚进程每种状态，

多进程编程

 1  
 2   
 3 # 功能 ： 创建新的进程
 4 # 参数 ： 无
 5 # 返回值 : 失败--->返回一个负数
 6 #  成功--->在新的进程中返回 ‘0’
 7 # 在原有的进程中返回新的进程的PID号
 8 import os
 9 pid = os.fork()
10 pid = os.fork()
11 print(pid)
12 
13 \'\'\'打印
14 9352
15 0
16 9353
17 \'\'\'

子进程会复制父进程的全部代码，包括fork之前产生的内存空间
子进程从fork的下一句开始执行，与父进程互不干扰
父子进程的执行顺序不一定，父子进程公用一个终端显示
父子进程通常会根据fork返回值的差异选择执行不同的代码。所以if结构几乎是fork的标配
父子进程空间独立，操作都是本空间的内容，互不影响
子进程也有自己的特性，比如PID号，PCB，命令集等。

进程相关的函数

函数方法	参数	说明
os.getpid()		返回当前进程的PID号
os.getppid()		返回当前进程的父进程的PID号
os._exit( status )	程序的退出状态	进程退出
sys.exit( [ status ] )	数字：表示退出状态，不写默认为	进程退出

import os
pid = os.fork()
if pid < 0:
    print("创建进程失败")
elif pid == 0:
    print("子进程我的真实PID为：",os.getpid(),"我的父进程PID为：",os.getppid())
else:
    print("我是父进程执行的代码,当前的变量pid为：",pid,"我的真实PID为：",os.getpid())
    
\'\'\'打印内容\'\'\'\'\'\'
我是父进程执行的代码,当前的变量pid为： 10992 我的真实PID为： 10991
子进程我的真实PID为： 10992 我的父进程PID为： 10991
\'\'\'\'\'\'打印内容\'\'\'
    
# 如果pid 10992和子进程真实PID不同，那么这个子进程就变成了孤儿进程

多进程模块

import multiprocessing

from multiprocessing import Process

Process()

功能：创建一个进程对象
参数
- name：进程名称
- target：绑定函数
- args：元组，给target函数按照位置传参
- kwargs：字典，给target函数按照键值对传参
- name: 字符串，新的进程的名字
- 例如：p = Process(target = fun,args=(a,b))

函数方法	说明
p.start()	启动进程，target函数自动执行，此时进程被真正创建
p.join([timeout])	阻塞等待回收子进程，timeout为超时时间
p.is_alive()	判断进程生命周期状态，处于生命周期，返回布尔值
p.name()	获取进程名称
p.pid()	获取进程的pid
p.daemon()	默认状态False，主进程退出不影响子进程。True :子进程随着主进程结束

使用multiprocessing创建子进程，同样子进程复制父进程的全部代码，父子进程各自执行互不影响，父子进程有各自的运行空间
如果不使用join挥手子进程则子进程退出后会成为僵尸进程

from multiprocessing import Process 
from time import sleep 

#带参数的进程函数
def worker(sec,name):
    for i in range(3):
        sleep(sec)
        print("I\'m %s"%name)
        print("I\'m working...")

p = Process(target = worker,args = (2,),\
    kwargs = {\'name\':\'Daivl\'},name = "Worker")
p.start()

print("Process name:",p.name) #进程名称
print("Process PID:",p.pid) #获取进程PID

#进程alive情况
print("Process is alive:",p.is_alive())

p.join(3)
print("==================")

创建自定义继承Process类

继承Process
编写自己的__init__，同时加载父类的__init__方法
重写run方法，可以通过生成的对象调用start自动运行

from  import Process
import time

class ClockProcess(Process):

    def __init__(self,value):
        self.value = value
        super(ClockProcess,self).__init__()

    def run(self):
        for i in range(5):
            print("现在的时间是",time.ctime())
            time.sleep(self.value)

# 创建自定义进的类的对象
p =ClockProcess(2)

# 自动调用run
p.start()
p.join()

进程池技术

产生原因
- 如果有大量任务需要多进程完成。则需要频繁的创建删除进程，给计算机带来较多的资源消耗
原理
- 创建适当的进程放入进程池，用来池里待处理的时间，处理完当前任务后进程不销毁，仍然哎进程池等待处理其他时间，进程的复用降低了系统资源的消耗
使用方法
1. 创建进程池，在池内放入适当的进程
2. 将事件加入到事件等待队列
3. 不断取进程执行时间，直到所有进程执行完毕
4. 关闭进程池，回收进程

Pool函数

Pool(Processes)
- 功能：创建进程池对象
- 表示进程池中有多少进程
pool.apply_async(func, args, kwds)
- 功能：将时间放入进程池队列
- 参数
  - func：事件函数
  - args：以元组形式给func传参
  - kwds ：以字典形式给func传参
- 返回值一个对象
pool.apply(func, args, kwds)
- 功能：将时间放入进程池队列
- 参数
  - func：事件函数
  - args：以元组形式给func传参
  - kwds ：以字典形式给func传参
pool.close()
- 功能：关闭进程池
pool.join()
- 功能：回收进程池
pool.map(func,iter)
- 功能：将要做的事件放入进程池
- 参数
  - func : 要执行的函数
  - iter ：迭代对象
- 返回值：多次return的结果列

from multiprocessing import Process
import time

class ClockProcess(Process):

    def __init__(self,value):
        self.value = value
        super(ClockProcess,self).__init__()

    def run(self):
        for i in range(5):
            print("现在的时间是",time.ctime())
            time.sleep(self.value)

# 创建自定义进的类的对象
p =ClockProcess(2)

# 自动调用run
p.start()
p.join()

进程间的通讯（IPC）

进程间通讯的方法有：管道，消息队列，共享内存，信号，信号量，套接字

	管道	消息队列	共享内存
开辟空间	内存	内存	内存
读写方式	两端读写[双向/单向]	先进先出	覆盖之前的内容
效率	一般	一般	较高
应用	多用于父子进程	广泛灵活	需要注意互斥

管道通讯

通信原理：在内存中开辟管道空间，生成管道操作对象，多个进程使用“同一个”管道对象进行操作，即可实现通信

multiprocessing –> Pipe

fd1,fd2 = Pipe(duplex = True)
- 功能：创建管道
- 参数
  - 默认表示为双向管道
  - 设置False则为单向管道
- 返回值
  - 如果是双向管道则都可以读写
  - 如果是单向管道，则fd1只读，fd2只写
fd.recv()
- 功能：从管道读取信息
- 返回值：读取到的内容
- 如果管道为空则堵塞
fd.send(data)
- 功能：向管道中写入内容
- 参数：要写入的内容
- 可以发送任意Python数据类型

多进程管道传输数据示例

from multiprocessing import Process,Pipe
import time,os

# 创建管道对象
fd1, fd2 = Pipe()

def fun(name):
    time.sleep(1)
    fd2.send(os.getppid())

jobs = []
# 创建5个子进程
for i in range(5):
    p = Process(target = fun,args = (i,))
    jobs.append(p)
    p.start()

for i in range(5):
    data = fd1.recv()
    print(data)

for i in jobs:
    i.join()

消息队列

队列：先进先出，按照顺序来

通信原理：在内存中建立队列数据结构模型。多个进程都可以通过队列存入内容，取出内容的顺序和存入的顺序保持一致

创建队列

q = Queue(maxsize = 0)
- 功能：创建队列消息
- 参数：表示最多存储多少消息。默认表示根据内存分配存储
- 返回值：队列对象
q.put(data, [block, timeout])
- 功能：像队列存储消息
- 参数
  - data：要存的内容
  - block：默认队列满时候会堵塞，设置False则非堵塞
  - timeout：超时时间
data = q.get([block, timeout])
- 功能：获取队列消息
- 参数
  - block：默认设置队列空时会堵塞，设置为False则非堵塞
  - timeout：超时时间
- 返回值：返回取出的内容
q.full()：判断队列是否为满
q.empty()：判断队列是否为空
q.size()：判断队列中的消息数量
q.close：关闭队列

单进程示例

#！《 单进程 》
from multiprocessing import Queue
from time import sleep

# 创建队列，可以放3条消息
q = Queue(3)
# 存一条消息
q.put(1)
sleep(0.5)
# 判断队列是否为空
print(q.empty())
q.put(2)
# 判断队列是否满
print(q.full())
q.put(3)
# 输出队列消息数量
print(q.qsize())
# 输出
print(q.get())
q.close()

多进程消息队列传递数据

from multiprocessing import Queue,Process
from time import sleep

# 创建队列，可以放3条消息
q = Queue(3)

def fun1():
    sleep(1)
    q.put({"a":1,"b":2})

def fun2():
    sleep(2)
    print("收到消息",q.get())

p1 = Process(target = fun1)
p2 = Process(target = fun2)
p1.start()
p2.start()
p1.join()
p2.join()

共享内存

通信原理：在内存中开辟一段空间，对多个进程可见，进程可以写入可以读，但是每次写入的内容会覆盖上一次的内容。

只能进行单个数据的发送

obj = Value(ctype, obj)

功能：开辟共享内存空间
参数
- ctype：要存储的数据类型
- obj：共享内存的初始数据
返回值：共享内存对象
obj.value即共享内存值，对其修改即可修改内存

from multiprocessing import Value
from time import sleep
import os
# 创建共享内存对象
money = Value(\'i\',2000)

# 操作共享内存
def deposite():
    while True:
        i = int(input("请输入："))
        money.value = i
        sleep(0.05)

def withdraw():
    data = money.value
    while True:
        if data != money.value :
            data = money.value
            print(data)
            
pid = os.fork()
if pid == 0 :
    deposite()
withdraw()

obj = Array(ctype, obj)

功能：开辟共享内存空间
参数：
- ctype：要存入的数据格式
- obj：初始化存入的内容，比如列表、字符串。如果是数字则代表开辟内存空间的个数
返回值：返回共享内存对象，可以遍历

from multiprocessing import Array,Process
from time import sleep
import os

# 开辟100字符内存空间，\'c\'代表字符，\'i\'代表整形
shm = Array(\'c\',100)
# 必须使用字节流
shm.value = "哈哈哈".encode()
def fun1():
    print(os.getpid(),"子进程1：",shm.value.decode())
    shm.value = "夜夜夜".encode()

def fun2():
    sleep(1)
    print(os.getpid(), "子进程2：",shm.value.decode())

p1 = Process(target = fun1)  
p2 = Process(target = fun2)
p1.start()
p2.start()
p1.join()
p2.join()

信号通信

一个进程向另一个进程发送一个信号来传递某种信息，接受者根据传递的信息来做相应的事

$ kill -l查看系统信号说明

$ kill -9 pid号对进程发送信号

信号名称	说明
1) SIGHUP	连接断开
2) SIGINT	ctrl+c
3) SIGQUIT	ctrl+\
20) SIGTSTP	ctrl+z
9) SIGKILL	终止进程
19) SIGSTOP	暂停进程
26) SIGVTALRM	时钟信号
17) SIGCHLD	子进程退出时给父进程发的信号

在Python中import signal可以获取信号

os.kill(pid, sig)
- 功能：发送信号
- 参数
  - pid：要发送信号的PID号
  - sig ：信号名称

import os
import signal
os.kill(12345,signal.SIGKILL) #杀死进程

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@media print { body, html { border: 1px solid rgba(0, 0, 0, 0); height: 99%; break-after: avoid; break-before: avoid } #write { margin-top: 0; border-color: rgba(0, 0, 0, 0) !important } .typora-export * { -webkit-print-color-adjust: exact } html.blink-to-pdf { font-size: 13px } .typora-export #write { padding-left: 1cm; padding-right: 1cm; padding-bottom: 0; break-after: avoid } .typora-export #write::after { height: 0 } @page { margin-top: 20mm margin-right: 0 margin-bottom: 20mm margin-left: 0 } }
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a img, img a { cursor: pointer }
pre.md-meta-block { font-size: 0.8rem; min-height: 0.8rem; white-space: pre-wrap; background: rgba(204, 204, 204, 1); display: block; overflow-x: hidden }
p>img:only-child { display: block; margin: auto }
p>.md-image:only-child { display: inline-block; width: 100%; text-align: center }
#write .MathJax_Display { margin: 0.8em 0 0 }
.md-math-block { width: 100% }
.md-math-block:not(:empty)::after { display: none }
[contenteditable=”true”]:active, [contenteditable=”true”]:focus { outline: 0; box-shadow: none }
.md-task-list-item { position: relative; list-style-type: none }
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.md-task-list-item>input { position: absolute; top: 0; left: 0; margin-left: -1.2em; margin-top: calc(1em – 10px) }
.math { font-size: 1rem }
.md-toc { min-height: 3.58rem; position: relative; font-size: 0.9rem; border-radius: 10px }
.md-toc-content { position: relative; margin-left: 0 }
.md-toc-content::after, .md-toc::after { display: none }
.md-toc-item { display: block; color: rgba(65, 131, 196, 1) }
.md-toc-item a { text-decoration: none }
.md-toc-inner:hover { }
.md-toc-inner { display: inline-block; cursor: pointer }
.md-toc-h1 .md-toc-inner { margin-left: 0; font-weight: 700 }
.md-toc-h2 .md-toc-inner { margin-left: 2em }
.md-toc-h3 .md-toc-inner { margin-left: 4em }
.md-toc-h4 .md-toc-inner { margin-left: 6em }
.md-toc-h5 .md-toc-inner { margin-left: 8em }
.md-toc-h6 .md-toc-inner { margin-left: 10em }
@media screen and (max-width: 48em) { .md-toc-h3 .md-toc-inner { margin-left: 3.5em } .md-toc-h4 .md-toc-inner { margin-left: 5em } .md-toc-h5 .md-toc-inner { margin-left: 6.5em } .md-toc-h6 .md-toc-inner { margin-left: 8em } }
a.md-toc-inner { font-size: inherit; font-style: inherit; font-weight: inherit; line-height: inherit }
.footnote-line a:not(.reversefootnote) { color: inherit }
.md-attr { display: none }
.md-fn-count::after { content: “.” }
code, pre, samp, tt { font-family: var(–monospace) }
kbd { margin: 0 0.1em; padding: 0.1em 0.6em; font-size: 0.8em; color: rgba(36, 39, 41, 1); background: rgba(255, 255, 255, 1); border: 1px solid rgba(173, 179, 185, 1); border-radius: 3px; box-shadow: 0 1px rgba(12, 13, 14, 0.2), inset 0 0 2px rgba(255, 255, 255, 1); white-space: nowrap; vertical-align: middle }
.md-comment { color: rgba(162, 127, 3, 1); opacity: 0.8; font-family: var(–monospace) }
code { text-align: left; vertical-align: initial }
a.md-print-anchor { white-space: pre !important; border-style: none !important; display: inline-block !important; position: absolute !important; width: 1px !important; right: 0 !important; outline: 0 !important; background: left top !important; text-shadow: initial !important }
.md-inline-math .MathJax_SVG .noError { display: none !important }
.md-math-block .MathJax_SVG_Display { text-align: center; margin: 0; position: relative; text-indent: 0; max-width: none; max-height: none; min-height: 0; min-width: 100%; width: auto; overflow-y: hidden; display: block !important }
.MathJax_SVG_Display, .md-inline-math .MathJax_SVG_Display { width: auto; display: inline-block !important }
.MathJax_SVG .MJX-monospace { font-family: var(–monospace) }
.MathJax_SVG .MJX-sans-serif { font-family: sans-serif }
.MathJax_SVG { display: inline; font-style: normal; font-weight: 400; line-height: normal; zoom: 90%; text-indent: 0; text-align: left; text-transform: none; letter-spacing: normal; word-spacing: normal; word-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0; min-height: 0; border: 0; padding: 0; margin: 0 }
.MathJax_SVG * { }
.MathJax_SVG_Display svg { vertical-align: middle !important; margin-bottom: 0 !important }
.os-windows.monocolor-emoji .md-emoji { font-family: “Segoe UI Symbol”, sans-serif }
.md-diagram-panel>svg { max-width: 100% }
[lang=”mermaid”] svg, [lang=”flow”] svg { max-width: 100% }
[lang=”mermaid”] .node text { font-size: 1rem }
table tr th { border-bottom: 0 }
video { max-width: 100%; display: block; margin: 0 auto }
iframe { max-width: 100%; width: 100%; border: none }
.highlight td, .highlight tr { border: 0 }
.CodeMirror { height: auto }
.CodeMirror.cm-s-inner { }
.CodeMirror-scroll { overflow-y: hidden; overflow-x: auto; z-index: 3 }
.CodeMirror-gutter-filler, .CodeMirror-scrollbar-filler { background-color: rgba(255, 255, 255, 1) }
.CodeMirror-gutters { border-right: 1px solid rgba(221, 221, 221, 1); white-space: nowrap }
.CodeMirror-linenumber { padding: 0 3px 0 5px; text-align: right; color: rgba(153, 153, 153, 1) }
.cm-s-inner .cm-keyword { color: rgba(119, 0, 136, 1) }
.cm-s-inner .cm-atom, .cm-s-inner.cm-atom { color: rgba(34, 17, 153, 1) }
.cm-s-inner .cm-number { color: rgba(17, 102, 68, 1) }
.cm-s-inner .cm-def { color: rgba(0, 0, 255, 1) }
.cm-s-inner .cm-variable { color: rgba(0, 0, 0, 1) }
.cm-s-inner .cm-variable-2 { color: rgba(0, 85, 170, 1) }
.cm-s-inner .cm-variable-3 { color: rgba(0, 136, 85, 1) }
.cm-s-inner .cm-string { color: rgba(170, 17, 17, 1) }
.cm-s-inner .cm-property { color: rgba(0, 0, 0, 1) }
.cm-s-inner .cm-operator { color: rgba(152, 26, 26, 1) }
.cm-s-inner .cm-comment, .cm-s-inner.cm-comment { color: rgba(170, 85, 0, 1) }
.cm-s-inner .cm-string-2 { color: rgba(255, 85, 0, 1) }
.cm-s-inner .cm-meta { color: rgba(85, 85, 85, 1) }
.cm-s-inner .cm-qualifier { color: rgba(85, 85, 85, 1) }
.cm-s-inner .cm-builtin { color: rgba(51, 0, 170, 1) }
.cm-s-inner .cm-bracket { color: rgba(153, 153, 119, 1) }
.cm-s-inner .cm-tag { color: rgba(17, 119, 0, 1) }
.cm-s-inner .cm-attribute { color: rgba(0, 0, 204, 1) }
.cm-s-inner .cm-header, .cm-s-inner.cm-header { color: rgba(0, 0, 255, 1) }
.cm-s-inner .cm-quote, .cm-s-inner.cm-quote { color: rgba(0, 153, 0, 1) }
.cm-s-inner .cm-hr, .cm-s-inner.cm-hr { color: rgba(153, 153, 153, 1) }
.cm-s-inner .cm-link, .cm-s-inner.cm-link { color: rgba(0, 0, 204, 1) }
.cm-negative { color: rgba(221, 68, 68, 1) }
.cm-positive { color: rgba(34, 153, 34, 1) }
.cm-header, .cm-strong { font-weight: 700 }
.cm-del { text-decoration: line-through }
.cm-em { font-style: italic }
.cm-link { text-decoration: underline }
.cm-error { color: rgba(255, 0, 0, 1) }
.cm-invalidchar { color: rgba(255, 0, 0, 1) }
.cm-constant { color: rgba(38, 139, 210, 1) }
.cm-defined { color: rgba(181, 137, 0, 1) }
div.CodeMirror span.CodeMirror-matchingbracket { color: rgba(0, 255, 0, 1) }
div.CodeMirror span.CodeMirror-nonmatchingbracket { color: rgba(255, 34, 34, 1) }
.cm-s-inner .CodeMirror-activeline-background { }
.CodeMirror { position: relative; overflow: hidden }
.CodeMirror-scroll { height: 100%; outline: 0; position: relative; box-sizing: content-box }
.CodeMirror-sizer { position: relative }
.CodeMirror-gutter-filler, .CodeMirror-hscrollbar, .CodeMirror-scrollbar-filler, .CodeMirror-vscrollbar { position: absolute; z-index: 6; display: none }
.CodeMirror-vscrollbar { right: 0; top: 0; overflow: hidden }
.CodeMirror-hscrollbar { bottom: 0; left: 0; overflow: hidden }
.CodeMirror-scrollbar-filler { right: 0; bottom: 0 }
.CodeMirror-gutter-filler { left: 0; bottom: 0 }
.CodeMirror-gutters { position: absolute; left: 0; top: 0; padding-bottom: 30px; z-index: 3 }
.CodeMirror-gutter { white-space: normal; height: 100%; box-sizing: content-box; padding-bottom: 30px; margin-bottom: -32px; display: inline-block }
.CodeMirror-gutter-wrapper { position: absolute; z-index: 4; background: left top !important; border: none !important }
.CodeMirror-gutter-background { position: absolute; top: 0; bottom: 0; z-index: 4 }
.CodeMirror-gutter-elt { position: absolute; cursor: default; z-index: 4 }
.CodeMirror-lines { cursor: text }
.CodeMirror pre { border-radius: 0; border-width: 0; background: left top; font-family: inherit; font-size: inherit; margin: 0; white-space: pre; word-wrap: normal; color: inherit; z-index: 2; position: relative; overflow: visible }
.CodeMirror-wrap pre { word-wrap: break-word; white-space: pre-wrap; word-break: normal }
.CodeMirror-code pre { border-right: 30px solid rgba(0, 0, 0, 0); width: fit-content }
.CodeMirror-wrap .CodeMirror-code pre { border-right: none; width: auto }
.CodeMirror-linebackground { position: absolute; left: 0; right: 0; top: 0; bottom: 0; z-index: 0 }
.CodeMirror-linewidget { position: relative; z-index: 2; overflow: auto }
.CodeMirror-wrap .CodeMirror-scroll { overflow-x: hidden }
.CodeMirror-measure { position: absolute; width: 100%; height: 0; overflow: hidden; visibility: hidden }
.CodeMirror-measure pre { position: static }
.CodeMirror div.CodeMirror-cursor { position: absolute; visibility: hidden; border-right: none; width: 0 }
.CodeMirror div.CodeMirror-cursor { visibility: hidden }
.CodeMirror-focused div.CodeMirror-cursor { visibility: inherit }
.cm-searching { background: rgba(255, 255, 0, 0.4) }
@media print { .CodeMirror div.CodeMirror-cursor { visibility: hidden } }
:root { –side-bar-bg-color: #fafafa; –control-text-color: #777 }
@font-face { font-family: “Open Sans”; font-style: normal; font-weight: normal; src: local(“Open Sans Regular”), url(“./github/400.woff”) format(“woff”) }
@font-face { font-family: “Open Sans”; font-style: italic; font-weight: normal; src: local(“Open Sans Italic”), url(“./github/400i.woff”) format(“woff”) }
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@font-face { font-family: “Open Sans”; font-style: italic; font-weight: bold; src: local(“Open Sans Bold Italic”), url(“./github/700i.woff”) format(“woff”) }
html { font-size: 16px }
body { font-family: “Open Sans”, “Clear Sans”, “Helvetica Neue”, Helvetica, Arial, sans-serif; color: rgba(51, 51, 51, 1); line-height: 1.6 }
#write { max-width: 860px; margin: 0 auto; padding: 20px 30px 100px }
#write>ul:first-child, #write>ol:first-child { margin-top: 30px }
body>:first-child { margin-top: 0 !important }
body>:last-child { margin-bottom: 0 !important }
a { color: rgba(65, 131, 196, 1) }
h1, h2, h3, h4, h5, h6 { position: relative; margin-top: 1rem; margin-bottom: 1rem; font-weight: bold; line-height: 1.4; cursor: text }
h1:hover a.anchor, h2:hover a.anchor, h3:hover a.anchor, h4:hover a.anchor, h5:hover a.anchor, h6:hover a.anchor { text-decoration: none }
h1 tt, h1 code { font-size: inherit }
h2 tt, h2 code { font-size: inherit }
h3 tt, h3 code { font-size: inherit }
h4 tt, h4 code { font-size: inherit }
h5 tt, h5 code { font-size: inherit }
h6 tt, h6 code { font-size: inherit }
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h4 { font-size: 1.25em }
h5 { font-size: 1em }
h6 { font-size: 1em; color: rgba(119, 119, 119, 1) }
p, blockquote, ul, ol, dl, table { margin: 0.8em 0 }
li>ol, li>ul { margin: 0 }
hr { height: 2px; padding: 0; margin: 16px 0; background-color: rgba(231, 231, 231, 1); border: 0 none; overflow: hidden; box-sizing: content-box }
body>h2:first-child { margin-top: 0; padding-top: 0 }
body>h1:first-child { margin-top: 0; padding-top: 0 }
body>h1:first-child+h2 { margin-top: 0; padding-top: 0 }
body>h3:first-child, body>h4:first-child, body>h5:first-child, body>h6:first-child { margin-top: 0; padding-top: 0 }
a:first-child h1, a:first-child h2, a:first-child h3, a:first-child h4, a:first-child h5, a:first-child h6 { margin-top: 0; padding-top: 0 }
h1 p, h2 p, h3 p, h4 p, h5 p, h6 p { margin-top: 0 }
li p.first { display: inline-block }
ul, ol { padding-left: 30px }
ul:first-child, ol:first-child { margin-top: 0 }
ul:last-child, ol:last-child { margin-bottom: 0 }
blockquote { border-left: 4px solid rgba(223, 226, 229, 1); padding: 0 15px; color: rgba(119, 119, 119, 1) }
blockquote blockquote { padding-right: 0 }
table { padding: 0; word-break: initial }
table tr { border-top: 1px solid rgba(223, 226, 229, 1); margin: 0; padding: 0 }
table tr:nth-child(2n), thead { background-color: rgba(248, 248, 248, 1) }
table tr th { font-weight: bold; border-top: 1px solid rgba(223, 226, 229, 1); border-right: 1px solid rgba(223, 226, 229, 1); border-bottom: 0; border-left: 1px solid rgba(223, 226, 229, 1); text-align: left; margin: 0; padding: 6px 13px }
table tr td { border: 1px solid rgba(223, 226, 229, 1); text-align: left; margin: 0; padding: 6px 13px }
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table tr th:last-child, table tr td:last-child { margin-bottom: 0 }
.CodeMirror-lines { padding-left: 4px }
.code-tooltip { box-shadow: 0 1px 1px rgba(0, 28, 36, 0.3); border-top: 1px solid rgba(238, 242, 242, 1) }
.md-fences, code, tt { border: 1px solid rgba(231, 234, 237, 1); background-color: rgba(248, 248, 248, 1); border-radius: 3px; padding: 2px 4px 0; font-size: 0.9em }
code { background-color: rgba(243, 244, 244, 1); padding: 0 4px 2px }
.md-fences { margin-bottom: 15px; margin-top: 15px; padding: 8px 1em 6px }
.md-task-list-item>input { margin-left: -1.3em }
@media screen and (min-width: 914px) { }
@media print { html { font-size: 13px } table, pre { break-inside: avoid } pre { word-wrap: break-word } }
.md-fences { background-color: rgba(248, 248, 248, 1) }
#write pre.md-meta-block { padding: 1rem; font-size: 85%; line-height: 1.45; background-color: rgba(247, 247, 247, 1); border: 0; border-radius: 3px; color: rgba(119, 119, 119, 1); margin-top: 0 !important }
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#write>h6.md-focus::before { left: -1.5625rem; top: 0.285714rem }
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.md-tag { color: rgba(167, 167, 167, 1); opacity: 1 }
.md-toc { margin-top: 20px; padding-bottom: 20px }
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#typora-quick-open { border: 1px solid rgba(221, 221, 221, 1); background-color: rgba(248, 248, 248, 1) }
#typora-quick-open-item { background-color: rgba(250, 250, 250, 1); border-top: 1px solid rgba(254, 254, 254, 1); border-right: 1px solid rgba(229, 229, 229, 1); border-bottom: 1px solid rgba(229, 229, 229, 1); border-left: 1px solid rgba(238, 238, 238, 1) }
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header, .context-menu, .megamenu-content, footer { font-family: “Segoe UI”, Arial, sans-serif }
.file-node-content:hover .file-node-icon, .file-node-content:hover .file-node-open-state { visibility: visible }
.mac-seamless-mode #typora-sidebar { background-color: var(–side-bar-bg-color) }
.md-lang { color: rgba(180, 101, 77, 1) }
.html-for-mac .context-menu { –item-hover-bg-color: #E6F0FE }
.typora-export p, .typora-export .footnote-line { white-space: normal }
#MySignature { display: none; background-color: rgba(178, 232, 102, 0.65); border-radius: 10px; box-shadow: 1px 1px 1px rgba(107, 107, 107, 1); padding: 10px; line-height: 1.5; text-shadow: 1px 1px 1px rgba(255, 255, 255, 1); font-size: 16px; font-family: “Microsoft Yahei” }

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