gtk:entry-set-icon-from-icon-name (entry pos name)

entry -- a gtk:entry widget
pos -- a gtk:entry-icon-position value for the icon position
name -- a string for the icon name, or nil

Sets the icon shown in the text entry at the specified position from the current icon theme. If the icon name is not known, a "broken image" icon will be displayed instead. If the name argument is nil, no icon will be shown in the specified position.