Publishing Engine Programmer's Guide > The Arbortext Publishing Engine Sub-Process > Arbortext Publishing Engine Document Conversion > Conversion Processing > Applying a Stylesheet
  
Applying a Stylesheet
A stylesheet provides instructions on how to convert the input document to the output document. There are two stylesheet parameters, stylesheet, which can be specified with every output type, and export-stylesheet, which is only used when producing RTF output.
There are several kinds of stylesheets:
Arbortext Styler stylesheets (.style files) can contain definitions for several PTC APP, XSL, or FOSI stylesheets, each for a different output format. The conversion processor extracts and uses the appropriate PTC APP, XSL, or FOSI stylesheet for the target output type.
FOSI stylesheets (.fos files) provide instructions for transforming an XML or SGML document to HTML, PDF, or PostScript.
XSL stylesheets (.xsl files) provide instructions for transforming one XML or SGML document to another XML or SGML document. In some cases, the resulting document is the output of the conversion operation. In other cases, the XML document produced by the XSL transformation is the input to a further processing step.
.3fPTC APP template files provide instructions for transforming an XML or SGML document to PostScript or PDF.
Some conversion operations do not use stylesheet processing at all.
You can specify a stylesheet in the following ways:
as an absolute path and file name on the Arbortext PE server. To avoid exposing the path to the Arbortext Publishing Engine installation tree, a stylesheet path can be specified using a server-side variable, for example:
PE_HOME\doctypes\axdocbook\axdocbook.style
as a URL
You can update Arbortext PE sub-process stylesheets and then use f=init to clear all previously cached stylesheets without restarting the Arbortext PE Request Manager. By clearing the stylesheet cache, Arbortext PE sub-processes will use the updated stylesheet for the next request that uses it.