linux - bash 中使用的 -ex 选项是什么 | #!/bin/bash -ex 意思

Question

我们使用下面的脚本作为 EC2 实例的用户数据。我不明白 -ex 选项的用途是什么？

#!/bin/bash -ex

yum update -y
yum groupinstall -y "Web Server" "MySQL Database" "PHP Support"
service httpd start
chkconfig httpd on

Answer 1

根据Add tack e x on your bash shebang | #!/bin/bash -ex

Bash scripts can use various options on the shebang (#!/bin/bash). A more common one is: ‘#!/bin/bash -ex’.

-e Exit immediately if a command exits with a non-zero status.
-x Print commands and their arguments as they are executed.

In short, adding -ex to your #!/bin/bash will give verbose output and also will abort your script immediately if part of the script fails.