Skip to content
Related Articles

Related Articles

Python | os.truncate() method
  • Last Updated : 25 Jun, 2019

OS module in Python provides functions for interacting with the operating system. OS comes under Python’s standard utility modules. This module provides a portable way of using operating system dependent functionality.
os.truncate() method truncates the file corresponding to path so that it is at most length bytes in size. This function can support file descriptor too.

Syntax: os.truncate(path, length)

Parameters:
path: This parameter is the path or file descriptor of the file that is to be truncated.
length: This is the length of the file upto which file is to be truncated.

Return Value: This method does not returns any value.

Example #1 :



Using os.truncate() method to truncate a file using it’s path.




# Python program to explain os.truncate() method 
        
# importing os module 
import os 
    
# path 
path = 'C:/Users/Rajnish/Desktop/testfile.txt'
  
# Open the file and get
# the file descriptor associated
# with it using os.open() method
fd = os.open(path, os.O_RDWR|os.O_CREAT)
  
# String to be written
s = 'GeeksforGeeks - A Computer Science portal'
  
# Convert the string to bytes 
line = str.encode(s)
  
# Write the bytestring to the file 
# associated with the file 
# descriptor fd 
os.write(fd, line)
  
# Using os.truncate() method
# Using path as parameter
os.truncate(path, 10)
  
# Seek the file from beginning
# using os.lseek() method
os.lseek(fd, 0, 0)
  
# Read the file
s = os.read(fd, 15)
  
# Print string
print(s)
  
# Close the file descriptor 
os.close(fd)
Output:
b'GeeksforGe'

Example #2 :
Using os.truncate() method to truncate a file using a file descriptor




# Python program to explain os.truncate() method 
        
# importing os module 
import os 
    
# path 
path = 'C:/Users/Rajnish/Desktop/testfile.txt'
  
# Open the file and get
# the file descriptor associated
# with it using os.open() method
fd = os.open(path, os.O_RDWR|os.O_CREAT)
  
# String to be written
s = 'GeeksforGeeks'
  
# Convert the string to bytes 
line = str.encode(s)
  
# Write the bytestring to the file 
# associated with the file 
# descriptor fd 
os.write(fd, line)
  
# Using os.truncate() method
# Using fd as parameter
os.truncate(fd, 4)
  
# Seek the file from beginning
# using os.lseek() method
os.lseek(fd, 0, 0)
  
# Read the file
s = os.read(fd, 15)
  
# Print string
print(s)
  
# Close the file descriptor 
os.close(fd)
Output:
b'Geek'

 Attention geek! Strengthen your foundations with the Python Programming Foundation Course and learn the basics.  

To begin with, your interview preparations Enhance your Data Structures concepts with the Python DS Course. And to begin with your Machine Learning Journey, join the Machine Learning – Basic Level Course

My Personal Notes arrow_drop_up
Recommended Articles
Page :