# libxml2 {#setup-hook-libxml2}
Adds every file named `catalog.xml` found under the `xml/dtd` and `xml/xsl` subdirectories of each build input to the `XML_CATALOG_FILES` environment variable.
Chunks
e93c409d (1st chunk of `doc/hooks/libxml2.section.md`)
Title: libxml2 Setup Hook
Summary
This setup hook for libxml2 adds all `catalog.xml` files located in the `xml/dtd` and `xml/xsl` subdirectories of build inputs to the `XML_CATALOG_FILES` environment variable.