- Qt Creator Documentation
- Specify the environment for projects
- Qt Creator 21.0.0-beta1

Specify settings for quick fixes ◦ Use Qt Creator variables

# Specify the environment for projects

The environment for a project is determined according to a settings hierarchy:

By default, the environment in which Qt Creator was started is used and modified to include the Qt version. Depending on the selected Qt version, Qt Creator automatically sets the necessary environment variables. You can edit existing environment variables or add, reset, and unset variables based on your project requirements.

The final environment is specified separately for each kit. With project-specific environment settings you can change the environment for all kits that you use to build, deploy, and run the project simultaneously, rather than having to change it separately for each kit.

The changes are stored in the local project-specific `CMakeLists.txt.user` or `.pro.user` file, depending on the build system you use, such as CMake or qmake. Therefore, they are not suitable for sharing between developers or development PCs. To share settings, incorporate them into the build system. For example, if you use CMake, make the changes in the `CMakeLists.txt` file, and if you use qmake, make the changes in the `.pro` file.

## Globally change the environment

To globally change the environment from the one in which Qt Creator is started, select Preferences > Environment > System, and then select Change in Environment.

## Change the environment for a project

To change the system environment for a project from the one in which Qt Creator is started, select Projects > Project Settings > Project Environment.

You can edit existing environment variables or add, reset, unset, or temporarily disable variables.

## Specify the build environment

To specify the build environment to use for a kit, go to Projects > Build Settings and select Build Environment.

To change the values of environment variables for the build environment, select the variable and then select Edit. Enter the new value in the editor on the right side.

To add new variables, select Add.

### Clear the build environment

To build with a clean system environment, select Clear system environment. Qt Creator discards the current environment, and populates a clean system environment with the environment variables that the compilers and tools need. Therefore, the environment is never totally empty, even after you clear it.

## Specify the run environment

Qt Creator automatically selects the environment used for running the application based on the device type. To edit the environment or select another environment, go to Projects > Run Settings and select Environment.

When running on the desktop, the Build Environment is used by default, but you can also use the System Environment without the additions made to the build environment.

### Clean the run environment

To run in a clean system environment, select Clean Environment.

### Set the environment for all run configurations

To set environment variables for running and debugging applications, so that they don't affect Qt Creator itself, set environment variables for run configurations of all projects:

1. Go to Preferences > Build & Run > General.
2. Select Change in Application environment.
3. Set environment variables in Edit Environment.

For example, set `QT_FORCE_STDERR_LOGGING=1` to see application output in Application Output instead of a journal or system log.

Or, set `QT_MESSAGE_PATTERN` to add information to debugging messages.

### Use device environment

When you run applications on a mobile device connected to the computer, Qt Creator fetches information about the Device Environment from the device. Usually, it does not make sense to edit the device environment.

## Use environment variables from a file

In addition to manually entering environment variable values in Qt Creator, you can specify a file as the source for the environment variables. The file can be a simple text file containing the key and value pairs, or a script to be evaluated by the system shell.

To use a file as the source for the environment variables:

1. Go to any of the environment settings described above.
2. Select Get variables from text file or shell script.
3. Enter the path to the file.

See also Edit environment settings, Configure projects for building, Configure projects for running, and Use Qt Creator variables.

Specify settings for quick fixes ◦ Use Qt Creator variables