Learning Linux Shell Scripting - Second Edition

Inserting – the i command

The i command is used for inserting text above the current pattern space line. When we use the append command, new text is inserted after the current line, which is in the pattern buffer. In this similar-to-append command, the backslash is inserted after the i command.

Here is an example:

    $ cat shopping.txt
    Product     Quantity  Unit_Price  Total_Cost
    Apple       2          3            6
    Orange            2          .8           1.6
    Papaya            2          1.5          3
    Chicken     3          5            15
    Cashew      1          10           10 
    $ sed '/Apple/i                                         
           New Prices will apply from Next month ! ' shopping.txt
  

The output is as follows:

    Product     Quantity  Unit_Price  Total_Cost
           New Prices will apply from Next month ! 
    Apple          2      3            6
    Orange         2       .8          1.6
    Papaya         2      1.5          3
    Chicken        3      5           15
    Cashew         1     10           10
  

In this example, the new text, New Prices will ...