The Environment

• The environment is the set of all exported variables
• An exported shell variable is added to the environment
• A process can access and use any of the variables in its environment
• One way to influence a process is to alter its environment:
  • Use the export command to add a new variable to the list
  • Modify the value of an exported variable before running a program
  • Modify an exported variable within a shell script
  • Make a temporary addition to or modification of the environment with the following construction:
    name=value command
    This causes the variable definition to hold only for the duration of the command.