When used as a return type, which Rust type plays a similar role to Python's None, JavaScript's null, or the void type in C/C++?

Which statement about the Clone and Copy traits is false?

What smart pointer is used to allow multiple ownership of a value in various threads?

Which types are not allowed within an enum variant's body?

Your application requires a single copy of some data type T to be held in memory that can be accessed by multiple threads. What is the thread-safe wrapper type?

Which choice is not valid loop syntax?

Race conditions are caused by which of the following conditions in a multi threaded system?

An orphan process occurs as a result of which of the following conditions?

When a new process is created using fork(), which of the following describes the state of open file descriptors?

Which of the following is correct for the standard file descriptors that are automatically opened in UNIX?

Which of the following could the fork() command return to the child process?