python os.pipe() 方法

python os 文件/目录方法

os.pipe() 方法用于创建一个管道, 返回一对文件描述符(r, w) 分别为读和写。

语法

pipe()方法语法格式如下：

os.pipe()

参数

• 无

返回值

返回文件描述符对。

实例

以下实例演示了 pipe() 方法的使用：

#!/usr/bin/python
# -*- coding: utf-8 -*-
import os, sys
print "the child will write text to a pipe and "
print "the parent will read the text written by child..."
# file descriptors r, w for reading and writing
r, w = os.pipe() 
processid = os.fork()
if processid:
    # this is the parent process 
    # closes file descriptor w
    os.close(w)
    r = os.fdopen(r)
    print "parent reading"
    str = r.read()
    print "text =", str   
    sys.exit(0)
else:
    # this is the child process
    os.close(r)
    w = os.fdopen(w, 'w')
    print "child writing"
    w.write("text written by child...")
    w.close()
    print "child closing"
    sys.exit(0)

执行以上程序输出结果为：

the child will write text to a pipe and
the parent will read the text written by child...
parent reading
child writing
child closing
text = text written by child...

python os 文件/目录方法