"Today's post is going to be on a relatively basic subject that
can elude a lot of folks who use sed casually. I, myself, for
years, only used it to print out matched patterns or do pattern
substitutions, but it's capable of much more than that. I don't
think it's quite up there with awk (insofar as the programming
functionality goes), but it does have lots of neat features (like
letting you switch between the current and hold buffer, for
example) that can sometimes make it the preferred tool for the job.
Especially if you're like me and you're not attached to any one
language or interpreter. My basic philosophy is: Whatever can get
it done the fastest and most efficiently. I think it works nicely,
as philosophies go, since I also compulsively automate
everything..."