Python os.fchdir()用法及代码示例

Python中的OS模块提供了与操作系统进行交互的函数。操作系统属于Python的标准实用程序模块。该模块提供了使用依赖于操作系统的函数的便携式方法。

os.fchdir()Python中的方法用于将当前工作目录更改为给定文件描述符表示的目录。

文件描述符是小整数值，与文件或其他输入/输出资源(例如管道或网络套接字)相对应。文件描述符是资源的抽象指示符，并充当执行各种较低级别I /O操作(如读取，写入，发送等)的句柄。

例如：标准输入通常是值为0的文件描述符，标准输出通常是值为1的文件描述符，标准错误通常是值为2的文件描述符。
当前进程打开的其他文件将获得值3、4、5，依此类推。

os.fchdir()方法等效于os.chdir(file_descriptor)方法。

用法： os.fchdir(fd)

参数：
fd：文件描述符。文件描述符必须代表打开的目录，而不是打开的文件。

返回类型：此方法不返回任何值。

代码1：使用os.fchdir()方法更改当前工作目录

# Python program to explain os.fchdir() method  
    
# importing os module  
import os 
  
  
# Print the current working 
# directory using os.getcwd() method 
print("Current working directory:", os.getcwd())  
   
  
# Path 
path = "/home/ihritik/Documents"
  
  
# open the directory represented by 
# the above given path and get 
# the file descriptor associated 
# with it using os.open() method 
fd = os.open(path, os.O_RDONLY) 
  
  
# Change the current working 
# directory using os.fchdir() method  
os.fchdir(fd) 
print("Current working directory changed")  
  
  
# Print the current working 
# directory using os.getcwd() method 
print("Current working directory:", os.getcwd())

输出：

Current working directory: /home/ihritik
Current working directory changed
Current working directory: /home/ihritik/Documents

代码2：使用os.fchdir()方法时可能出现的错误

# Python program to explain os.fchdir() method  
    
# importing os module  
import os 
  
  
# Path 
path = "/home/ihritik/Documents/file.txt"
  
# open the above path and get 
# the file descriptor associated 
# with it using os.open() method 
fd = os.open(path, os.O_RDONLY) 
  
  
# The file descriptor must  
# represent an open file  
# instead of an opened directory 
# The method will raise  
# 'NotADirectoryError' exception  
  
# Change the current working 
# directory using os.fchdir() method  
os.fchdir(fd) 
print("Current working directory changed")  
  
  
# Print the current working 
# directory using os.getcwd() method 
print("Current working directory:", os.getcwd())

输出：

Traceback (most recent call last):
  File "changeDir.py", line 24, in 
    os.fchdir(fd)
NotADirectoryError: [Errno 20] Not a directory

代码3：使用os.fchdir()方法时可能的错误处理

# Python program to explain os.fchdir() method  
    
# importing os module  
import os 
  
  
# Path 
path = "/home/ihritik/Desktop/file.txt"
  
# try opening the above path and get 
# the file descriptor associated 
# with it using os.open() method 
try : 
    fd = os.open(path, os.O_RDONLY) 
      
    # Try Changing the current working 
    # directory using os.fchdir() method  
    try : 
        os.fchdir(fd) 
        print("Current working directory changed")  
          
        # Print the current working 
        # directory using os.getcwd() method 
        print("Current working directory:", os.getcwd())  
  
  
    # Catch exceptions 
    # If file descriptor does 
    # not represents a directory 
    except NotADirectoryError: 
        print("The given file descriptor does \ 
not represent a directory") 
      
  
# Catch exceptions 
# If path does not exists 
except FileNotFoundError: 
    print("Path does not exists") 
  
# If there is any permission 
# related issue while opening 
# the given path  
except PermissionError: 
    print("Permission denied")

输出：

The given file descriptor does not represent a directory

相关用法

注：本文由纯净天空筛选整理自ihritik大神的英文原创作品 Python | os.fchdir() method。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。