Paper 16-126 on mixing defined I/O and asynchronous I/O seems to have missed this restriction: "Neither a parent nor child data transfer statement shall be asynchronous.? Cheers, Bill Bill Long longb at cray.com Fortran Technical Support & voice: 651-605-9024 Bioinformatics Software Development fax: 651-605-9142 Cray Inc./ Cray Plaza, Suite 210/ 380 Jackson St./ St. Paul, MN 55101