How to insert multiple lines into a batch of text files on Linux system with sed
How to insert multiple lines into a batch of text files on Linux system with sed

Question description This question come from when I want to insert Google Analytics code into HTML files. Let's have a look on the code. <!-- Global site tag (gtag.js) - Google Analytics --> <script async src="https://www.googletagmanager.com/gtag/js?id=UA-155361814-3"></script> <script> window.dataLayer = window.dataLayer || []; function gtag(){dataLayer.push(arguments);} gtag('js', new Date()); gtag('config', 'UA-155361814-3'); </script> I run four sites on... » read more