Summary
This chapter examined the world of Linux environment variables. Global environment variables can be accessed from any child shell spawned by the parent shell in which they're defined. Local environment variables can be accessed only from the process in which they're defined.
The Linux system uses both global and local environment variables to store information about the system environment. You can access this information from the shell command line interface, as well as within shell scripts. The bash shell uses the system environment variables defined in the original Unix Bourne shell, as well as lots of new environment variables. The PATH
environment variable defines the search pattern the bash shell takes to find an executable command. You can modify the PATH
environment variable to add your own directories, or even the current directory symbol, to make running your programs easier.
You can also create your own global and local environment variables for your own use...