In COMPIL (1.4) and COMPLP (BASICplus) modes, the I switch causes ISAM 1.x statements to be accepted (and in the case of ambiguous open statements, for ISAM 1.x to be assumed). Otherwise, old ISAM statements are only accepted in OCMPIL mode. New file type open specifiers ISAM’INDEXED{‘EXCLUSIVE} and ISAMP’INDEXED{‘EXCLUSIVE} can be use to avoid ambiguity and to allow both ISAM 1.x and ISAM-A to coexist in the same program.