Concepts

oatbar configuration is built around four main concepts that work together to display information.

• Bar ([[bar]]): The top-level window and layout container.
• Block ([[block]]): Visual widgets (text, images, graphs) displayed on the bar.
• Command ([[command]]): External programs that fetch data.
• Variable ([[var]]): Named data holders populated by commands and used by blocks.

Data Flow

1. Command runs (e.g., date) and outputs text.
2. oatbar parses the output and updates a Variable (e.g., ${clock:value}).
3. Block references the variable in its value property (e.g., value="Time: ${clock:value}").
4. Bar re-renders the block with the new text.

Variable Interpolation

String properties in blocks support variable interpolation using the ${...} syntax.

Syntax

• Basic: ${command_name:variable_name}
• With Property: ${command_name:variable_name.property} (for complex data like i3bar JSON).
• Filters: ${variable|filter:arg} (e.g., ${cpu|align:>3}).

Example

[[command]]
name="clock"
command="date +%H:%M"
interval=60

[[block]]
name="my_clock"
type="text"
value="Time: ${clock:value}"

Debugging

Use oatctl to inspect the current state of variables and blocks.

# List all active variables and their values
oatctl var ls