>> Peter, do you agree that Linux appears to differ from POSIX here? (Not >> sure if you tried my test program to verify...) > > > I did run the test program to validate that it's observed behavior is that > implemented by Linux, with which I'm very familiar. > I don't have a test setup for other *nixes. > > I would be interested to know the results of > > ./noncanonical 0 5 3 0 > hello Solaris 10: read() completes when 5 bytes received. OpenBSD 5.4 read() completes when 5 bytes received. > and > > ./noncanonical 0 5 3 2 > hel Solaris read blocks() OpenBSD read blocks Plus my test case where Linux differs: ./noncanonical 100 5 3 0 Linux: read() returns after 3 bytes input Solaris: read() returns only after 5 bytes input OpenBSD: read() returns only after 5 bytes input > on other platforms. > > With respect to POSIX compliance, it's hard to say. I'm not sure the > spec contemplates the degenerate case where max bytes < MIN. And Well, given the way the other implementations behave, I think it does contemplate it, because it carefull avoids talking about the number of bytes requested by read() in that case. > specifically > with regard to terminal i/o behavior, POSIX is essentially ex post facto, > and is really documenting existing behavior. > > Other than the degenerate case of max bytes < MIN, is there any other > variation between Solaris and Linux in non-canonical mode? The only one I've seen is the one I noted. I haven't tested too exhaustively though. Cheers, Michael -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ Linux/UNIX System Programming Training: http://man7.org/training/ -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
