Python File Readline() Method

Description

Python file method readline()reads one entire line from the file. A trailing newline character is kept in the string. If the size argument is present and non-negative, it is a maximum byte count including the trailing newline and an incomplete line may be returned.

An empty string is returned only when EOF is encountered immediately.

Syntax

Following is the syntax for readline() method:

fileObject.readline( size );

Parameters

• size - This is the number of bytes to be read from the file.

Return Value

This method returns the line read from the file.

Example

The following example shows the usage of readline() method.

This is 1st line
This is 1nd line
This is 2rd line
This is 3th line
This is 4th line
This is 5th line

#!/usr/bin/python

# Open a file
fo = open("foo.txt", "rw+")
print "Name of the file: ", fo.name

# Assuming file has following 5 lines
# This is 1st line
# This is 2nd line
# This is 3rd line
# This is 4th line
# This is 5th line

line = fo.readline()
print "Read Line: %s" % (line)

line = fo.readline(5)
print "Read Line: %s" % (line)

# Close opend file
fo.close()

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

Name of the file: foo.txt
Read Line: This is 1st line

Read Line: This  

Here at Intellinuts, we have created a complete Python tutorial for Beginners to get started in Python.