Command line

When Sympathy is installed in your python environment you can run python -m sympathy to access the command line interface.

For a comprehensive list of commands and options, see All command line options.

Top-level commands

Running python -m sympathy --help will print the top level commands available.


run Sympathy in GUI mode


run Sympathy in CLI mode


run the viewer for sydata files


generate documentation files


install Sympathy (start menu, file associations)


uninstall Sympathy (start menu, file associations)


run the test suite


cleanup temporary files

Command options

As mentioned there are several top level commands. Most of which have their own options.

In order to list the options available for a command, run sympathy adding the desired command and --help to the command line. For example, python -m sympathy gui --help shows the available options for running Sympathy in GUI mode.

Noteable examples

Here are a few examples that might be useful, for the full list please use the --help flag.

Run Sympathy for Data GUI:

python -m sympathy gui

Run Sympathy for Data CLI, executing a specified syx-workflow-file:

python -m sympathy cli filename

Build documentation for Sympathy for the platform and standard library.

python -m symapthy_app install --generate-docs

Run the test suite

python -m symapthy_app tests -v


Depending on how Sympathy was installed, you might also have shortcuts available to some commands.

Wheel installer:

sympathy (python -m sympathy) sympathy cli (python -m sympathy cli) sympathy gui (python -m sympathy gui)

Windows installer:

RunSympathyCLI.bat (python -m sympathy cli) RunSympathyGUI.bat (python -m sympathy gui)

Using environment variables

Environment variable expansion is useful in node configurations where the node should behave differently depending on the environment where it is executed. A simple example would be a workflow that always loads a certain file from the current user’s home directory. To achieve that you can simply configure a Datasource node to point to $(HOME)/somefile.txt and it will point to the file somefile.txt in the user’s home directory.

Apart from using already existing OS environment variables you can also add your own environment variables at three different levels: OS/shell, workflow, and global. Workflow level variables are generally preferred as they do not risk affecting workflows that they should not affect.

Default workflow environment variables

A few variables are always defined in every workflow. $(SY_FLOW_FILEPATH) holds the full path to the workflow file, and $(SY_FLOW_DIR) contains the directory of the workflow file. These variables behave just like normal workflow variables, but they are not stored in a syx-file. Instead they are computed on the fly when they are used. Check properties for a flow to see what values these variables have for that flow.

Adding OS/shell environment variables

Setting environment variables or shell variables is done differently depending on operating system, version, shell, and so on. As an example let us set the shell variable GREETING and start Sympathy in a command prompt in Windows:

> set GREETING=Hi!
> RunSympathyGUI.exe

Add a Hello world example node and configure it to display $(GREETING). Run the node. The output should be Hi!.

Adding workflow environment variables

Workflow level environment variables can be added and removed via the preferences GUI. Right click in your flow and click Properties and go to the tab Environment variables, where you can add, change, and remove workflow variables. These variables are stored in the workflow file, and will only affect that workflow, and its subflows. A subflow can always override a variable set by one of its parent flows.

Adding environment variables to the global file

Just as workflow level variables, global variables can be added and edited in:ref:Environment Preferences<preferences_environment> but they are stored in the global config file for Sympathy so they affect all workflows.


In case of name conflicts, environment variables are looked up in the following order:

  1. OS/shell

  2. Workflow (defined in current subflow)

  3. Workflow (defined in a parent workflow)

  4. Global settings

Special variables


Used to override the folder where session data (temporary files) are stored. The temporary path may in turn contain environment variables.