How are unicode strings converted to ansi for external functions?

[kgpkgp]

Hi,

Migrating from PB6 to PB12. I have some external functions written in C that expect strings in ISO-8859-7 encoding. When using the ANSI convention of calling external functions, does PB assume that unicode Strings are in English? Is there a way to make powerbuilder convert to a specific encoding before calling the external function?

Thanks.