| ENV | |
| --- | |
| Operator to read environment variables. | |
| Use the syntax ``$ENV{VAR}`` to read environment variable ``VAR``. | |
| To test whether an environment variable is defined, use the signature | |
| ``if(DEFINED ENV{<name>})`` of the :command:`if` command. | |
| .. note:: | |
| Environment variable names containing special characters like parentheses | |
| may need to be escaped. (Policy :policy:`CMP0053` must also be enabled.) | |
| For example, to get the value of the Windows environment variable | |
| ``ProgramFiles(x86)``, use: | |
| .. code-block:: cmake | |
| set(ProgramFiles_x86 "$ENV{ProgramFiles\(x86\)}") | |
| For general information on environment variables, see the | |
| :ref:`Environment Variables <CMake Language Environment Variables>` | |
| section in the :manual:`cmake-language(7)` manual. |