-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 According to Christopher Faylor on 6/18/2005 9:45 AM: > IMO, the posted check for fifos is flawed in that it assumes that > writing to a fifo will not block if there is no reader on the fifo. > That's not true for cygwin.
The posted check for fifos used the O_NONBLOCK flag when opening the fifo for writing, and POSIX requires that write() on an non-blocking fifo must not block. If this is not the case, then cygwin fifos are still broken. But when O_NONBLOCK is not set, you are correct that cygwin (and in fact, any implementation) can block on write() when there are no readers. However, the posted test also mentions in its comment that fifos with O_RDWR mode are used for BROKEN_PIPE and select() under 386BSD, and O_RDWR mode on fifos is non-portable (not specified by POSIX). Thus, cygwin has no requirements to make O_RDWR match what any other implementation might do, and portable programs should not be using O_RDWR on fifos. One other comment, is that the original poster's complaint showed that configure sleeps for 5 seconds, but the fifo test code calls alarm(5). Tto ensure that the conftest.exe has completed, configure could be changed to sleep for 6 seconds, rather than guessing which process (the sleep, or conftest.exe) will wake up first. - -- Life is short - so eat dessert first! Eric Blake [EMAIL PROTECTED] -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.0 (Cygwin) Comment: Public key at home.comcast.net/~ericblake/eblake.gpg Comment: Using GnuPG with Thunderbird - http://enigmail.mozdev.org iD8DBQFCuqzn84KuGfSFAYARAnTiAKC8B3UWKSfTLAylYxQ86TktUahS8QCgrpuj rmTCw5bsUXU0nz7Tfscl/kI= =YPRL -----END PGP SIGNATURE----- -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/
