详解程序意外中断自动重启shell脚本（以Python为例）

cd Desktopvim run.sh #新建名为run的shell脚本

#!/bin/bashwhile [ 1 ];do python run.pydone

chmod 777 run.sh #设置shell脚本权限./run.sh   #运行shell脚本

nohup ./run5.py &

import osclass UrlManager(object): def __init__(self):						#建立两个数组的文件  with open('new_urls.txt','r+') as new_urls:   self.new_urls = new_urls.read()  with open('old_urls.txt','r+') as old_urls:   self.old_urls = old_urls.read() def add_new_url(self, url): 				 #添加url到new_ulrs文件中  if url is None:   return  if url not in self.new_urls and url not in self.old_urls:   with open('new_urls.txt', 'a') as new_urls:    new_urls.write(url)  else:   print('url had done') def add_new_urls(self, urls):				#添加多个url到new_ulrs文件中  # if urls is None or (len(url) == 0 for url in urls):  if urls is None:   print('url is none')   return  for url in urls:   if urls is None:    print('url is none')    return   else:    self.add_new_url(url) def has_new_url(self):  return len(self.new_urls) != 0 def get_new_url(self):				  new_url = get_last_line('new_urls.txt') 	#读取new_urls文件中最后一个url  del_last_url('new_urls.txt',new_url)		#删除new_urls文件中最后一个url  add_old_urls('old_urls.txt',new_url)		#将读取出来的url添加入old_urls数组中  return new_url	def get_last_line(inputfile):	 filesize = os.path.getsize(inputfile)	 blocksize = 1024	 dat_file = open(inputfile, 'rb')		 last_line = b""	 lines = []	 if filesize > blocksize:	  maxseekpoint = (filesize // blocksize) # 这里的除法取的是floor	  maxseekpoint -= 1	  dat_file.seek(maxseekpoint * blocksize)	  lines = dat_file.readlines()	  while ((len(lines) < 2) | ((len(lines) >= 2) & (lines[1] == b'/r/n'))): # 因为在Windows下，所以是b'/r/n'	   # 如果列表长度小于2，或者虽然长度大于等于2，但第二个元素却还是空行	   # 如果跳出循环，那么lines长度大于等于2，且第二个元素肯定是完整的行	   maxseekpoint -= 1	   dat_file.seek(maxseekpoint * blocksize)	   lines = dat_file.readlines()	 elif filesize: # 文件大小不为空	  dat_file.seek(0, 0)	  lines = dat_file.readlines()	 if lines: # 列表不为空	  for i in range(len(lines) - 1, -1, -1):	   last_line = lines[i].strip()	   if (last_line != b''):	    break # 已经找到最后一个不是空行的	 dat_file.close()	 return last_line		def del_last_url(fname,part):	 with open(fname,'rb+') as f:	  a = f.read()	 a = a.replace(part,b'')	 with open(fname,'wb+') as f:	  f.write(a)	  	def add_old_urls(fname,new_url):	 line = new_url + b'/r'	 with open(fname,'ab') as f:	  f.write(line)