Session Variables

Variables that control your environment.


The exec Command

The exec command can be used to replace the current program with another or to redirect <std-in> or <std-out> for your session.


The (...) and {...;} Contructs

(...) can be used to group a set of commands and redirect input and output.  Commands are run in a separate shell.

{...; } can be used the same way, except it runs in the current shell.