Read a File and Redirect the Output to the Same File
To write outputs to a file in a shell, we can use redirection. However, when we read a file and modify the content and redirect to the same original file, we'll get just an empty file. What's going on here?
$ cat file bravo delta charlie alpha charlie $ cat file | sort | uniq > file $ cat file # empty file $ Of course, if you redirect to a different file and rename it to the original name, it works as expected.
