Chaining Sed

Another benefit of using STDIN when working with sed is the ability to chain multiple substitutions (or other sed scripts). The final example of the last article was an example of chaining sed, but you will get another example here.

In an earlier walkthrough you corrected the user-data.csv.

It took a total of three steps to complete the task. However, you could have chained all of the steps together using the pipe (|) operator.

Let’s give it a try:

sed 's/mastercard/Mastercard/' user-data.csv | sed 's/spectrum/Spectrum/' | sed 's/Stephens-Griffin/Stephens-Griffin-Ferguson/' > user-data.corrected2.csv

Validation

cat user-data.corrected2.csv

There shouldn’t be any spectrum matches:

grep 'spectrum' user-data.corrected2.csv

There shouldn’t be any mastercard matches:

grep 'mastercard' user-data.corrected2.csv

There should only be one Stephens-Griffin-Ferguson match:

grep 'Stephens-Griffin-Ferguson' user-data.corrected2.csv

We did not provide the pictures as evidence, because you should have the skills now to validate these changes yourself.