Python os.dup2() Method

Python File(文件) 方法 Python OS File/Directory Methods

Overview

os.dup2() method is used to duplicate a file descriptor fd to another fd2.

Available on Unix, Windows.

Syntax

dup2()The method syntax format is as follows:

os.dup2(fd, fd2);

Parameters

fd-- The file descriptor to be duplicated
fd2-- The file descriptor to copy to

Return Value

No return value.

Example

The following example demonstrates the use of the dup2() method:

#!/usr/bin/python
# -*- coding: UTF-8 -*-

import os, sys

# 打开文件
fd = os.open( "foo.txt", os.O_RDWR|os.O_CREAT )

# 写入字符串
os.write(fd, "This is test")

# 文件描述符为 1000
fd2 = 1000
os.dup2(fd, fd2);

# 在新的文件描述符上插入数据
os.lseek(fd2, 0, 0)
str = os.read(fd2, 100)
print "读取的字符串是 : ", str

# 关闭文件
os.close( fd )

print "关闭文件成功!!"

The output of the above program is:

读取的字符串是 :  This is test
关闭文件成功!!