Learn Linux Shell Scripting - Fundamentals of Bash 4.4

In-place editing

While it is not that big a deal to cat a file before we send it to sed, fortunately, we don't really need to do that. The usage for sed is as follows: sed [OPTION] {script-only-if-no-other-script} [input-file]. As you can see at the end, there is an option for [input-file].

Let's take one of the previous examples, and remove the cat:

reader@ubuntu:~/scripts/chapter_10$ sed 's/wood/stone/g' search.txt How much stone would a stonechuck chuckif a stonechuck could chuck stone?reader@ubuntu:~/scripts/chapter_10$ cat search.txt How much wood would a woodchuck chuckif a woodchuck could chuck wood?

As you can see, by using the optional [input-file] argument, sed processes all lines in that file according to the script. By default, ...