FcConfigGetFilename - Find a config file
#include <fontconfig/fontconfig.h>
FcChar8 * FcConfigGetFilename (FcConfig *config, const FcChar8 *name);
Given the specified external entity name, return the associated filename. This
provides applications a way to convert various configuration file references
into filename form.
A null or empty name indicates that the default
configuration file should be used; which file this references can be
overridden with the FONTCONFIG_FILE environment variable. Next, if the name
starts with ~, it refers to a file in the current users home
directory. Otherwise if the name doesn't start with '/', it refers to a file
in the default configuration directory; the built-in default directory can
be overridden with the FONTCONFIG_PATH environment variable.
The result of this function is affected by the FONTCONFIG_SYSROOT
environment variable or equivalent functionality.