Sometimes, you need to execute several commands together. For example, if you want to perform a specific action in a different directory, you could use the code in Listing 8.
Listing 8. Execute several commands at the same time
# pwd /home/cormany # cd testdir # tar â€“cf ls_output.tar ls.out? # pwd /home/cormany/testdir
This works, but note that after the execution of theses steps, you're no longer in your original directory. By placing the commands into their own subshell, they execute as a single instance of the subshell. Listing 9 shows the same idea executed using a subshell.
Listing 9. Execute several commands at the same time using a subshell
# pwd /home/cormany # (cd testdir ; tar -cf ls_output.tar ls.out?) # pwd /home/cormany