<P> In all Unix and Unix - like systems , each process has its own separate set of environment variables . By default , when a process is created , it inherits a duplicate environment of its parent process , except for explicit changes made by the parent when it creates the child . At the API level , these changes must be done between running fork and exec . Alternatively , from command shells such as bash , a user can change environment variables for a particular command invocation by indirectly invoking it via env or using the ENVIRONMENT_VARIABLE = VALUE < command > notation . A running program can access the values of environment variables for configuration purposes . </P>
<P> In all Unix and Unix - like systems , each process has its own separate set of environment variables . By default , when a process is created , it inherits a duplicate environment of its parent process , except for explicit changes made by the parent when it creates the child . At the API level , these changes must be done between running fork and exec . Alternatively , from command shells such as bash , a user can change environment variables for a particular command invocation by indirectly invoking it via env or using the ENVIRONMENT_VARIABLE = VALUE < command > notation . A running program can access the values of environment variables for configuration purposes . </P>
which command will display all the environment variables on the system
which command will display all the environment variables on the system
ENVIRONMENT_VARIABLE = VALUE < command >
ENVIRONMENT_VARIABLE = VALUE < command >