| Date: Wed, 31 Jul 2002 15:13:23 +0100
| From: Ronan Cunniffe <ronan at cunniffe.net>
| Um, my test was to tee to a fifo I didn't read from... resulting
| in the other reader hanging around forever.... not realising that
| never-opened-for-reading and opened-and-later-closed might be
ah! yes! this is one of those gotchas everyone stumbles
over. the writer of a never-opened-for-reading pipe will
quickly block (as soon as the pipe's limited buffer fills
up). but the writer of opened-and-later-closed pipe gets
an EPIPE error (and the usually-terminal SIGPIPE signal).
the typical stumble is someone creates an anonymous pipe
with pipe(2), but forgets to close(2) the reader's fd in
the writer-process (or visa-versa) .... and then wonders
why the real reader never sees an EOF and/or the writer
is never gets an EPIPE/SIGPIPE. various FAQs and many
books probably discuss this topic in depth to the death.
| Sensible behaviour has now been observed.
good! and good luck.
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