io_uring_close_ring_fd(3) — Linux manual page


io_uring_close_ring_fd(3)    liburing Manual   io_uring_close_ring_fd(3)

NAME         top

       io_uring_close_ring_fd - close a ring file descriptor and use it
       only via registered index

SYNOPSIS         top

       #include <liburing.h>

       int io_uring_close_ring_fd(struct io_uring *ring);

DESCRIPTION         top

       io_uring_close_ring_fd(3) closes the ring file descriptor, which
       must have been previously registered.  The file will remain open,
       but accessible only via the registered index, not via any file
       descriptor. Subsequent liburing calls will continue to work,
       using the registered ring fd.

       The kernel must support IORING_FEAT_REG_REG_RING.

       Libraries that must avoid disrupting their users' uses of file
       descriptors, and must continue working even in the face of
       close_range(2) and similar, can use io_uring_close_ring_fd(3) to
       work with liburing without having any open file descriptor.

NOTES         top

       Each thread that wants to make use of io_uring must register the
       fd. A library that may get called from arbitrary theads may need
       to detect when it gets called on a previously unseen thread and
       create and register a ring for that thread.

RETURN VALUE         top

       Returns 1 on success, or -errno on error.

SEE ALSO         top


COLOPHON         top

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liburing-2.4               September 25, 2022  io_uring_close_ring_fd(3)

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