How Boolean variables are interpreted

When an environment variable is expressed as a Boolean, software interprets the value of the variable, when set, as follows:

• If the value starts with a letter, an uppercase “T” or a lowercase “t” or an uppercase “Y” or a lowercase “y”, the variable is interpreted as true. If the value starts with any other letter, the variable is interpreted as false.

• If the value can be interpreted as an integer variable, and it has a value of zero, the variable is interpreted as false. If the value is anything other than zero, the variable is interpreted as true.

• For any other value, the variable is interpreted as false.