site_archiver@lists.apple.com Delivered-To: darwin-dev@lists.apple.com On Jul 10, 2006, at 12:02 PM, darwin-dev-request@lists.apple.com wrote: Welcome to Unix. Please see the select(2) manpage, and Have a Nice Day! = Mike _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.appl... I am writing some code to work with an RS-232 serial device (via USB adapter). It basically works. All the IOKit parts are fine, and I end up with a file descriptor and then use the posix read() and write() APIs. The read() man page says "The system guarantees to read the number of bytes requested if the descriptor references a normal file that has that many bytes left before the end-of-file, but in no other case." Indeed with my serial device, if I say to read 15 bytes it sometimes returns after reading 10 bytes. Is there anyway to have read() block until the requested length is ready? Is my only other choice some kind of loop that calls read() and usleep() over and over? If so, how do I choose a sleep duration? This email sent to site_archiver@lists.apple.com