Handling I/O and environment variables
In this section, we'll look at how to handle I/O with child processes, and also learn to set and clear environment variables for the child process.
Why would we need this?
Take the example of a load balancer that is tasked with spawning new workers (Unix processes) in response to incoming requests. Let's assume the new worker process reads configuration parameters from environment variables to perform its tasks. The load balancer process then would need to spawn the worker process and also set its environment variables. Likewise, there may be another situation where the parent process wants to read a child process's standard output or standard error and route it to a log file. Let's understand how to perform such activities in Rust. We'll start with handling the I/O of the child process.
Handling the I/O of child processes
Standard input (stdin), standard output (stdout), and standard error (stderr) are...
