Jayson Nordwick wrote:
> If you find an available signal, set the handler for it, the block it,
> this signal number now effectively becomes the completion port. You then
> can fcntl() a file descriptor with F_SETSIG and the signal number. Then to
> fetch the blocked signals, use sigwaitinfo(). I guess you could also use
> aio_{read,write}() and set sigevent appropriately. This actually seems
> preferable since you can then use aio_return() to find the return value
> out and use aio_cancel() to cancel the request if wanted.
You probably don't need the aio_*() interfaces to be honest. It's just as easy
to set the socket nonblocking and deal with the event system as it is.
> Basically, unless anybody can see anything wrong with this get to work
> implementing!
I really haven't seen any examples of how to work with the event system.
Attached to this message is a basic example using sigwaitinfo() for linux
2.2.x and glibc 2.1. Once si_band information is integrated into the stable
tree, this will actually be an effective way to eliminate polling, although it
could use a bit of speeding up.
If I have made any mistakes, please email me. There wasn't that much
documentation on how to do it correctly.
Jordan
-- Jordan Mendelson : http://jordy.wserv.com Web Services, Inc. : http://www.wserv.com --------------15876512C7F918C24B551AB4 Content-Type: application/x-unknown-content-type-cfile; name="sigio2.c" Content-Transfer-Encoding: base64 Content-Disposition: inline; filename="sigio2.c"LyoqKgogKiBTSUdJTzIuQyAtIEZ1biB3aXRoIHNpZ25hbHMKICoKICogVGhpcyBpcyBhIHZl cnkgc2ltcGxlIGV4YW1wbGUgd2hpY2ggcmVhZHMgc3RhbmRhcmQgaW5wdXQgYW5kIHByaW50 cwogKiB2aWEgc3RhbmRhcmQgb3V0cHV0LiBJdCB1c2VzIHNpZ3dhaXRpbmZvKCkgaW5zdGVh ZCBvZiBhIHNpZ25hbCBoYW5kbGVyCiAqIHRvIGRlcXVldWUgc2lnbmFscy4KICoKICogSSBh dHRlbXB0ZWQgdG8gbWFrZSB0aGlzIGFzIFBPU0lYJ2x5IGNvcnJlY3QgYXMgcG9zc2libGUs IGJ1dCB3aXRob3V0CiAqIGFjY2VzcyB0byByZWFsIFBPU0lYIGRvY3VtZW50YXRpb24sIEkg aGFkIHRvIHJlbHkgb24gb25saW5lIGluZm9ybWF0aW9uCiAqIHdoaWNoIHdhcyB2YWd1ZSBh dCBiZXN0LgogKgogKiBVbmxpbWl0ZWQgcmVkaXN0cmlidXRpb24gYW5kIG1vZGlmaWNhdGlv biBvZiB0aGlzIHNvdXJjZSBpcyBncmFudGVkLgogKgogKiBKb3JkYW4gTWVuZGVsc29uIChq 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