ProOutputFileWrite Arg2 value - Documentation incomplete for STEP file

Need to write some code to autocreate STEP files for a qty of parts.  Seems simple enough.  However, the TKwizard description for arg2 in incomplete.   It says " arg2 is a int* pointing to the number."    number of what?

Has anyone used ProOutputfileWriet to create a step files and know what arg2 does?