Remove the last empty line from each text file

Question

I have many text files, and each of them has a empty line at the end. My scripts did not seem to remove them. Can anyone help please?

# python 2.7
import os
import sys
import re

filedir = 'F:/WF/'
dir = os.listdir(filedir)

for filename in dir:
    if 'ABC' in filename: 
        filepath = os.path.join(filedir,filename)
        all_file = open(filepath,'r')
        lines = all_file.readlines()
        output = 'F:/WF/new/' + filename

        # Read in each row and parse out components
        for line in lines:
            # Weed out blank lines
            line = filter(lambda x: not x.isspace(), lines)

            # Write to the new directory 
            f = open(output,'w')
            f.writelines(line)
            f.close() 

Answer 1

You can use Python's rstrip() function to do this as follows:

filename = "test.txt"

with open(filename) as f_input:
    data = f_input.read().rstrip('\n')

with open(filename, 'w') as f_output:    
    f_output.write(data)

This will remove all empty lines from the end of the file. It will not change the file if there are no empty lines.

Answer 2

you can remove last empty line by using:

with open(filepath, 'r') as f:
    data = f.read()
    with open(output, 'w') as w:
        w.write(data[:-1])