Writing Output and Exit Codes
Report results and signal status.
Tools Talk Back
Reading input is half the job. A finished CLI also writes output and signals success or failure to whatever ran it. 📤
Two Output Streams
Programs have two channels: stdout for normal results and stderr for messages and errors. Keeping them separate lets users pipe results cleanly.
All lessons in this course
- Reading Command-Line Arguments
- Reading Files and stdin
- Writing Output and Exit Codes
- Package and Release the Binary