Python 3 - File readlines() Method


The 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.


Following is the syntax for readlines() method −

fileObject.readlines( sizehint );


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

Return Value

This method returns a list containing the lines.


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

Assuming that 'foo.txt' file contains following text:
This is 1st line
This is 2nd line
This is 3rd line
This is 4th line
This is 5th line


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

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

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

# Close opened file


When we run the above program, it produces the 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\n']
Read Line: