What bash command can be used for regex substitution on a pipe?

     cat foo.txt | someprogram

You probably want

sed 's/exp1/exp2/g' foo.txt > foo2.txt

Read more at Sed tutorial, Another tutorial, and A small tutorial at Linux HOWTOs

  • sed isn't just a program, it's a way of life. Jun 15 '09 at 11:24

You can also use perl one liners if you find you want more regular expression features than sed provides. See this link for a comparison. nik's example would look like:

perl -ple 's/exp1/exp2/g' foo > foo2.txt
  • I recently discovered perl -pe, and it's great to have a much more powerful regex engine available :) Jan 22 '10 at 15:10

The program you are looking for is sed.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.