Python File readlines() Method

Description

Python file method readlines() reads until EOF using readline() and returns a list containing the lines. If the optional sizehint argument is present, instead of reading up to EOF, whole lines totalling approximately sizehint bytes (possibly after rounding up to an internal buffer size) are read.

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

Syntax

Following is the syntax for readlines() method −

fileObject.readlines( sizehint );

Parameters

sizehint − This is the number of bytes to be read from the file.

Return Value

This method returns a list containing the lines.

Example

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

This is 1st line
This is 2nd line
This is 3rd 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.readlines()
print "Read Line: %s" % (line)

line = fo.readlines(2)
print "Read Line: %s" % (line)

# Close opend file
fo.close()

When we run above program, it produces following result −

Name of the file:  foo.txt
Read Line: ['This is 1st line\n', 'This is 2nd line\n', 'This is 3rd line\n', 'This is 4th line\n', 'This is 5th line']
Read Line: []

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