What does /dev/tty do and when should I use it?

/dev/tty can be used in lots of scenarios in bash. It's there to access the terminal associated with your current session. For instance, when you want to ensure that output or error messages show up right on the terminal and not get redirected elsewhere, using /dev/tty can be your best friend. A use-case could be something like this: `cat files* | awk -f script | tee /dev/tty | sort > output`. It's all about making sure you're getting the right information displayed on your terminal when working with multiple input streams.

You were tripped up because you were trying to read from both tar's output and inputting responses from the terminal, which essentially is why your script wasn’t working. When you use read from /dev/tty, it explicitly tells the script to expect input from the terminal itself, avoiding those conflicts. You could also try using different file descriptors to separate those input streams for more complex scenarios. Though, honestly, many seasoned users would say you don't *need* to read from /dev/tty; it’s often considered messy and maybe not even POSIX compliant.

Sometimes you might not even have access to /dev/tty, like when executing commands over ssh. In those cases, the command can’t rely on using /dev/tty, which is why it’s important to understand alternative outputs and error handling. When you’re in interactive or local contexts, using /dev/tty has its place, but beware of where you're calling your scripts from!