On Apr 11, 2008, at 9:08 , John Goerzen wrote:
On Fri April 11 2008 8:02:07 am Brandon S. Allbery KF8NH wrote:
On Apr 11, 2008, at 8:12 , John Goerzen wrote:
OK, I have referred to fifo(7) regarding this point.  It seems I
may need a
loop trying over and over to open the FIFO in write mode.  It also
appears
that ReadWriteMode appearing to work is Linux-specific, and this
behavior is
left undefined in POSIX.

Undefined in POSIX, normal for Unix (and Linux originally promised
only POSIX semantics but was rejiggered some years back to behave
like Unix in this regard, because Unix programs rely on these
semantics and therefore failed on Linux).

Hrm, can you define what OSs you mean when you say "Unix"?

SunOS/Solaris, and in general the descendants of 4.xBSD and AT&T System III/V. Unless this is a different issue from the usual FIFO only-works-as-expected-if-both-ends-always-open problem. That is, unless the first opener opens read/write, neither a prospective writer nor a prospective reader will be capable of opening it at all; depending on OS you will get ENXIO or EPIPE or (in some rare implementations) EAGAIN.

--
brandon s. allbery [solaris,freebsd,perl,pugs,haskell] [EMAIL PROTECTED]
system administrator [openafs,heimdal,too many hats] [EMAIL PROTECTED]
electrical and computer engineering, carnegie mellon university    KF8NH


_______________________________________________
Haskell-Cafe mailing list
Haskell-Cafe@haskell.org
http://www.haskell.org/mailman/listinfo/haskell-cafe

Reply via email to