Some Systems type Stuff

• Command Line Arguments.
  • import sys
  • sys.argv is an array of arguments.
  • see argv.py
• The systems module (sys)
  • Access to interpreter variables.
• Environment Variables
  • import os
  • os.environ is a dictionary of the environment variables.
  • see env.py
• The os module in general
  • Portable operating system dependant functions.
  • Limited by os used.
  • os.name
  • getguid, geteuid, getpid, getppid, setuid, ...
  • dup, chmod,
• An example from before:
  • a bytes object is a sequence of bytes.
    • These are used for low level io at least.
    • string.encode() converts a string to a bytes object.
    • string.decode() brings it back.
  • Remeber the lseek example.
  • seeker.py
• Homework 6
  • os has a scandir command
    • This returns a os.DirEntry
    • That has a name
    • path
  • I can get a os.stat result
  • And an pwd password file entry