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head command in unix

 

 

Head Command Examples

The head command in unix or linux system is used to print the first N lines from the file to the terminal. The syntax of head command is 

head [options] [files]


The head command options are: 

·                       c : Prints the first N bytes of file; With leading -, prints all but the last N bytes of the file.

·                       n : Prints first N lines; With leading - print all but the last N lines of each file.


Head Command Examples: 
Create the following file in your linux or unix operating system for practicing the examples: 

> cat example.txt

linux storage

ubuntu os

fedora


1. Display first 10 lines 

By default, the head command prints the first 10 lines from a file. 

> head example.txt


2. Display first N lines 

Use the -n option to print the first n lines from a file. The following example prints the first 2 lines from the file: 

> head -n2 example.txt

linux storage

ubuntu os


3. Skip last N lines 

You can skip the last N lines from a file and print the remaining lines. The following example skips the last 2 lines and prints the remaining lines. 

> head -n-2 example.txt

linux storage


4. Print the first n bytes. 

use the -c option to print the first N bytes from the file. The following example prints the first 5 bytes from the file. 

> head -c5 example.txt

linux


5. Skip printing last n bytes. 

Use the leading "-", to skip printing last N bytes. 

> head -c-7 example.txt

linux storage

ubuntu os


6. Print line between M and N lines. 

You can combine the head command with tail command to print lines between the line numbers M and N. The following command prints the lines between numbers 5 and 10. 

> head -n10 filename | tail -5

 

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