Inserting Text in Files Using ANSI-C Quoting in OSX with sed

When working with text files on OSX, the sed (stream editor) command proves to be a powerful tool for making automated edits. One common task involves inserting lines into specific positions within files. This article explores how to use sed with ANSI-C quoting to achieve this.

Introduction to sed

sed is a Unix utility that parses and transforms text, using a simple and compact programming language. It is commonly used for text substitution, deletion, and insertion tasks.

ANSI-C Quoting

ANSI-C quoting allows the use of escape sequences in string literals, facilitating the insertion of complex strings and multi-line texts. This is particularly useful when working with sed for inserting text into files.

Inserting Text Using sed and ANSI-C Quoting

Let's break down the process of inserting text at a specific line in a file using sed on OSX. The general syntax for inserting text at a specific line is:

``bash

sed -i '' 'N i\text to insert' file

`

Where:

  • -i '' enables in-place editing of the file.
  • 'N i\text to insert' specifies the line number N and the text to insert.

Example 1: Inserting a Line at a Specific Position

To insert a line at the 3rd position in a file, the following command is used:

`bash

sed -i '' '3i\'