Book Image

Linux Shell Scripting Essentials

By : Sinny Kumari, Khem Raj
Book Image

Linux Shell Scripting Essentials

By: Sinny Kumari, Khem Raj

Overview of this book

Table of Contents (15 chapters)
Linux Shell Scripting Essentials
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Sorting and finding unique text


Shell provides different ways to sort the input text using the sort command. It's also possible to remove repeated lines from sorted/unsorted input text using the uniq command. The input text to sort and uniq commands can be given from a file, or redirected from another command.

Sorting an input text

The lines in the input text are sorted in the following order:

  • Numbers from 0 to 9

  • Uppercase letters from A to Z

  • Lowercase letters from a to z

The syntax will be as follows:

sort [OPTION] [FILE …]

Single or multiple input files can be provided to sort for sorting.

The sort command takes multiple options to provide flexibility in sorting. The popular and important OPTION to sort have been discussed in the following table:

Option

Description

-b

This ignores leading blanks

-d

This considers only blanks and alphanumeric characters

-f

This ignores a case

-i

This ignores a non-printable character

-M

This compares months that are unknown (for example,...