Title: Port of the week: entr Author: Solène Date: 07 January 2017 Tags: unix Description: **entr** is a command line tool that let you run arbitrary command on file change. This is useful when you are doing something that requires some processing when you modify it. Recently, I have used it to edit a man page. At first, I had to run mandoc each time I modified to file to check the render. This was the first time I edited a man page so I had to modify it a lot to get what I wanted. I remembered about **entr** and this is how you use it: $ ls stagit.1 | entr mandoc /_ modified. The file names must be given by stdin to entr, and then use the characters sequence **/_** to replace the names (like {} in find). The man page of entr is very well documented if you need more examples.