include/linux/aio_abi.h and IOCB_CMD_POLL

[Goswin von Brederlow <goswin-v-b@web.de>]

Hi,

please CC me on replies.

I'm trying to write a fuse filesystem in ocaml using asynchronous
IO. For that to work nicely I need to poll /dev/fuse for incoming
requests without reading data from it (libfuse does that when called,
I just need to know when I can call it without it blocking).

Now to my problem. The header file for libaio says:

| /* Jeff Moyer says this was implemented in Red Hat AS2.1 and RHEL3.
|  * AFAICT, it was never in mainline, and should not be used. --RR */
| static inline void io_prep_poll(struct iocb *iocb, int fd, int events)

I tried using it anyway but all I got was an error that /dev/fuse is
not seekable. I also looked in the kernel source and didn't see any
implementation for poll there.

So my questions now are:

1) Why was this never adapted into mainline?
2) Do you know if there is any patch for it against a recent kernel?
3) Are there any alternatives to libaio that don't use threads and
   support polling?

MfG
        Goswin