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#POSIX Polling — kqueue Backend

c
#define FIO_POLL_ENGINE_KQUEUE
#define FIO_POLL
#include "fio-stl.h"

Implementation of the portable polling API on top of BSD/macOS kqueue. Normally selected automatically when <sys/event.h> is available; define FIO_POLL_ENGINE_KQUEUE to force it.

The public API is documented in 102 poll api.md. This file describes backend-specific behavior.

#Backend Details

#struct fio_poll_s

c
struct fio_poll_s {
  fio_poll_settings_s settings;
  int fd;
};

A single kqueue descriptor is used for both read and write filters.

#fio_poll_engine

Returns "kqueue".

#Fork Safety

A state callback re-creates the kqueue descriptor in the child process after fork.

#Notes

  • Read and write filters are registered with EV_ADD | EV_ENABLE | EV_CLEAR | EV_ONESHOT.
  • EV_EOF and EV_ERROR flags are routed to on_close.
  • fio_poll_review uses a timespec built from the millisecond timeout.