-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 According to Eric Blake on 7/6/2009 7:03 AM: > But on cygwin 1.7, when you attempt to create multiple writers to a single > fifo, the second writer creates an fd just fine but then fails on any > attempt to write to that fd: > > $ mkfifo fifo > $ (exec 5>fifo; sleep 25; echo one >&5)& > [1] 4200 > $ (exec 5>fifo; sleep 15; echo two >&5)& > [2] 204
It appears that part of the problem is that cygwin is violating POSIX - a process that opens a fifo for writes must block until a corresponding process opens the same fifo for reads, but cygwin is creating the fd without blocking. A pstree at this point shows that the sleep processes have already been spawned... > $ exec 5<fifo ...even though on Linux, the sleeps cannot spawn until after this point. - -- Don't work too hard, make some time for fun as well! Eric Blake e...@byu.net -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (Cygwin) Comment: Public key at home.comcast.net/~ericblake/eblake.gpg Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iEYEARECAAYFAkpR+DsACgkQ84KuGfSFAYBfLQCfY+IozoBQWjQaohizEcOjgXLt CMYAoMTHprULJoeVp+i38N4Kjrv/HCHq =VCM7 -----END PGP SIGNATURE----- -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
