Below is a quest function for getting the instance flag of a character.
Zone\perlparser.cpp
Above XSRETURN_YES;
Insert
	Code:
	newXS(strcpy(buf, "getinstflag"), XS__getinstflag, file);
 zone\perlparser.cpp
Above /*This is the callback perl will look for to setup the
Insert
	Code:
	XS(XS__getinstflag);
XS(XS__getinstflag)
{
    dXSARGS;
    if (items != 0)
        Perl_croak(aTHX_ "Usage: getinstflag()");
    int		RETVAL;
    dXSTARG;
	RETVAL = quest_manager.getinstflag();
	XSprePUSH; PUSHu((IV)RETVAL);
	XSRETURN(1);
}
 Zone\questmgr.h
Near line 179 Insert 
zone\questmgr.cpp
At end Insert
	Code:
	int QuestManager::getinstflag()
{
	return (database.GetCharInstFlagNum(initiator->CharacterID()));
}