That is an interesting comment. DMR was on the steering committee for what would become 4.2BSD. I once spoke with Kirk McKusick about the origins of the sockets API and I think he told me that there was a lot of debate in the committee whether descriptor readiness API should be stateful (like Haverty’s await() https://www.tuhs.org/cgi-bin/utree.pl?file=BBN-V6/ken/awaitr.c ) or stateless (like select). According to Sam Leffler (who I think added select() to 4.1c BSD) the select system call was somewhat modelled after the ADA select statement. I am speculating now, but I would not be surprised if dmr favoured the stateless design and contributed to its design. Paul