os.fdatasync() Method

Description

The method fdatasync() forces write of file with filedescriptor fd to disk. This does not force update of metadata. If you want to flush your buffer then you can use this method.

Syntax

Following is the syntax for fdatasync() method −

os.fdatasync(fd)

Parameters

• fd − This is the file descriptor for which data to be written.

Return Value

This method does not return any value.

Example

The following example shows the usage of fdatasync() method −

import os, sys

# Open a file
fd = os.open( "foo.txt", os.O_RDWR|os.O_CREAT )

# Write one string
line="this is test"

# string needs to be converted byte object
b=str.encode(line)
os.write(fd, b)

# Now you can use fdatasync() method.
# Infact here you would not be able to see its effect.
os.fdatasync(fd)

# Now read this file from the beginning.
os.lseek(fd, 0, 0)
str = os.read(fd, 100)
line = os.read(fd, 100)
str=line.decode()
print ("Read String is : ", str)

# Close opened file
os.close( fd )
print ("Closed the file successfully!!")

When we run the above program, it produces the following result −

Read String is : This is test
Closed the file successfully!!