Customization of the 4.3 DocBook-XSL Stylesheets for the TCC

We stipulate that if a DocBook user uses callouts such as programlistingco, they must have a subdirectory named callout/ containing images named 1.png, 2.png, and so forth, to be used as the graphic for callouts 1, 2, ….

<xsl:param name="callout.graphics.path">callouts/</xsl:param>