How to manage and manipulate text data (e.g., awk, sed) in Bash?

To manage and manipulate text data in Bash, you can make use of various text-processing tools such as awk and sed. Here's a brief guide on how to use them:

  1. awk:

    • Awk is a powerful tool for processing text files and can be used to extract, transform, and manipulate data. It works by scanning input line by line, splitting lines into fields, and performing actions based on patterns and rules.
    • Basic usage: awk 'pattern { action }' file
    • To print specific columns from a file: awk '{ print $1, $3 }' file
    • To filter lines based on a condition: awk '$2 > 10 { print $0 }' file
    • There are many more advanced features available in awk, such as built-in functions, associative arrays, and user-defined functions.
  2. sed:

    • Sed (stream editor) is a simple yet powerful tool for filtering and transforming text. It operates on a line-by-line basis and applies commands to modify the input stream based on regular expression patterns.
    • Basic usage: sed 'command' file
    • To substitute text: sed 's/pattern/replacement/' file
    • To delete lines matching a pattern: sed '/pattern/d' file
    • To apply multiple commands: sed -e 'command1' -e 'command2' file
    • Similar to awk, sed offers more advanced features like pattern addresses, branches, and hold space.

These are just some examples of how you can manage and manipulate text data using awk and sed. Both tools are incredibly versatile and have extensive documentation available online.