void set_pattern(string pattern);

The pattern of underlines you want under the existing text within the GtkLabel widget.

For example if the current text of the label says "FooBarBaz" passing a pattern of "___ ___" will underline "Foo" and "Baz" but not "Bar".

Example 91. Setting the Pattern of a GtkLabel

// Create a window to hold the label.
$window = new GtkWindow();

// Set up the window to close cleanly.
$window->connect_simple('destroy', array('Gtk', 'main_quit'));

// Create a label.
$label = new GtkLabel('FooBarBaz');

// Set the pattern.
$label->set_pattern('___   ___');

// Add the label to the window.

// Show the window and start the main loop.
This code will produce the window shown below.