Services or capabilities described in Amazon Web Services documentation might vary by Region. To see the differences applicable to the China Regions, see Getting Started with Amazon Web Services in China (PDF).

Using exit codes in commands

In some cases, you might need to manage how your commands are handled by using exit codes.

Specify exit codes in commands

Using Run Command, a capability of Amazon Systems Manager, you can specify exit codes to determine how commands are handled. By default, the exit code of the last command run in a script is reported as the exit code for the entire script. For example, you have a script that contains three commands. The first one fails but the following ones succeed. Because the final command succeeded, the status of the execution is reported as succeeded.

Shell scripts

To fail the entire script at the first command failure, you can include a shell conditional statement to exit the script if any command before the final one fails. Use the following approach.

<command 1>
    if [ $? != 0 ]
    then
        exit <N>
    fi
    <command 2>
    <command 3>

In the following example, the entire script fails if the first command fails.

cd /test
    if [ $? != 0 ]
    then
        echo "Failed"
        exit 1
    fi
    date

PowerShell scripts

PowerShell requires that you call exit explicitly in your scripts for Run Command to successfully capture the exit code.

<command 1>
    if ($?) {<do something>}
    else {exit <N>}
    <command 2>
    <command 3>
    exit <N>

Here is an example:

cd C:\
    if ($?) {echo "Success"}
    else {exit 1}
    date