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Spawning a separate process with subshell
Subshells are separate processes. A subshell is defined using the ( ) operators:
- The pwd command prints the path of the working directory
- The cd command changes the current directory to the given directory path:
$> pwd / $> (cd /bin; ls) awk bash cat... $> pwd /
When commands are executed in a subshell, none of the changes occur in the current shell; changes are restricted to the subshell. For example, when the current directory in a subshell is changed using the cd command, the directory change is not reflected in the main shell environment.