Prohibit reading from /dev/tty

Question

Tools like sudo read from /dev/tty to read a password.

I would like to avoid this.

The subprocess should not be able to read /dev/tty. The subprocess should fail immediately instead of waiting for input for ever.

I am using the subprocess module of Python. The subprocess should fail if it tries to read from /dev/tty.

Remember: The tool sudo is just an example. A fancy command line argument to sudo does not solve my problem. This should work for all linux command line tools.

Question: How to make any tool fail as soon as it wants to read from /dev/tty (called via the subprocess module of Python)?

Background: This is a normal linux user process, not root.

Answer 1

Since python3.2 Popen takes an argument start_new_session which will cause the executed process to be started detached from the current controlling terminal by calling setsid() prior to executing the child process.

So all you should need is to start the process with start_new_session=True