The selectors Module

Describing I/O Multiplexing

• The selectors module is used to multiplex processing across multiple input/output streams
• Specifically, it does this without using threads or subprocesses
• Multiplexing refers to observing multiple I/O streams
• We can also block I/O streams as well

• The selectors module does the following:

  • Wait for I/O event readiness on multiple files
  • Supports file stream registration
  • Waiting for I/O events on streams with optional timeouts

API for the BaseSelector Class

• register

  • Registers a file object for selection
  • Monitors the file for I/O events

• select

  • Waits until some registered file becomes ready or the timeout expires
  • Returns a list of (key, events) tuples
  • The elements of these tuples represent ready files

References

• Python Essential Reference
• Documentation for selectors API