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Step-by-Step Guide to Reading Different Files in Python

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 In the world of data science, automation, and general programming, working with files is unavoidable. Whether you’re dealing with CSV reports, JSON APIs, Excel sheets, or text logs, Python provides rich and easy-to-use libraries for reading different file formats. In this guide, we’ll explore how to read different files in Python , with code examples and best practices. 1. Reading Text Files ( .txt ) Text files are the simplest form of files. Python’s built-in open() function handles them effortlessly. Example: # Open and read a text file with open ( "sample.txt" , "r" ) as file: content = file.read() print (content) Explanation: "r" mode means read . with open() automatically closes the file when done. Best Practice: Always use with to handle files to avoid memory leaks. 2. Reading CSV Files ( .csv ) CSV files are widely used for storing tabular data. Python has a built-in csv module and a powerful pandas library. Using cs...
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Tail Command in Linux: A Comprehensive Overview

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The tail in Linux is handy command. You can check the last lines of a file in Linux/Unix operating systems.

You can use it to display last lines from single file, display last lines from multiple files, display the last entries of log files.


Tail Command in Linux


During production support the usage of Tail command is helpful since you can check latest logs quickly. Here are the top Tail command examples.

#1 Display last lines in a file (Tail file Linux)


Here's the tail command that shows last three lines of a file.

cat sample.txt | tail -3

It displays last 3 lines of a file. The same command you can use as

tail -3 sample.txt

#2 Display last lines of multiple files


There are three files. sample2.txt, sample3.txt, sample4.txt. The command displays the last 3 lines from all the three files.

tail -3 sample[2-4].txt


Tail command


#3 Tail -f option (Tail f Linux)


The –f option is to check status of long-running process that is redirecting output to a file. For example, if you invoke the below command, the status it writes to the output.

find . -print |xargs grep -i abc </tmp/abc &

Using the -f option you can see contents of the file /tmp/abc whenever it is updated: 

tail -f /tmp/abc


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