This script is simple, but we still need to know how to make use of the exit codes from scripts and other applications. The command-line list that we generated earlier, while creating the $HOME/bin directory, is a good example of how we can use the exit code:
$ command1 || command 2
In the preceding example, command2 is executed only if command1 fails in some way. To be specific, command2 will run if command1 exits with a status code other than 0.
Similarly, in the following extract, we will only execute command2 if command1 succeeds and issues an exit code of 0:
$ command1 && command2
To read the exit code from our script explicitly, we can view the $? variable, as shown in the following example:
$ hello1.sh
