time.sleep
有时候我们需要模拟程序的暂停,或者耗时。就需要让程序睡一会儿。
简介
Python time sleep() 函数推迟调用线程的运行,可通过参数secs指秒数,表示进程挂起的时间。
语法
time.sleep(t)
例子
#!/usr/bin/python
import time
print "Start : %s" % time.ctime()
time.sleep( 5 )
print "End : %s" % time.ctime()
个人使用案例
import scrapy
import os
import time
class CurlSpider(scrapy.Spider):
name = 'curlspider'
start_urls = ['https://blog.csdn.net/ryo1060732496']
# init curls
urls = []
path='data/blog.txt'
# 指定以 utf-8 的格式读取文件
with open(path, encoding='utf-8') as f:
for line in f:
urls.append(line)
def parse(self, response):
for url in self.urls:
cmd = "curl " + str(url)
print(cmd)
os.system(cmd)
## sleep
time.sleep(5)