io_uring_prep_write_fixed(3) — Linux manual page
io_uring_prep_write(3) liburing Manual io_uring_prep_write(3)
NAME
io_uring_prep_write_fixed - prepare I/O write request with
registered buffer
SYNOPSIS
#include <liburing.h>
void io_uring_prep_write_fixed(struct io_uring_sqe *sqe,
int fd,
const void *buf,
unsigned nbytes,
__u64 offset,
int buf_index);
DESCRIPTION
The io_uring_prep_write_fixed(3) prepares an IO write request
with a previously registered IO buffer. The submission queue
entry sqe is setup to use the file descriptor fd to start writing
nbytes from the buffer buf at the specified offset and with the
buffer matching the registered index of buf_index.
This works just like io_uring_prep_write(3) except it requires
the use of buffers that have been registered with
io_uring_register_buffers(3). The buf and nbytes arguments must
fall within a region specified by buf_index in the previously
registered buffer. The buffer need not be aligned with the start
of the registered buffer.
After the read has been prepared it can be submitted with one of
the submit functions.
RETURN VALUE
None
ERRORS
The CQE res field will contain the result of the operation. See
the related man page for details on possible values. Note that
where synchronous system calls will return -1 on failure and set
errno to the actual error value, io_uring never uses errno.
Instead it returns the negated errno directly in the CQE res
field.
SEE ALSO
io_uring_prep_write(3), io_uring_register_buffers(3)
COLOPHON
This page is part of the liburing (A library for io_uring)
project. Information about the project can be found at
⟨https://github.com/axboe/liburing⟩. If you have a bug report for
this manual page, send it to io-uring@vger.kernel.org. This page
was obtained from the project's upstream Git repository
⟨https://github.com/axboe/liburing⟩ on 2024-06-14. (At that
time, the date of the most recent commit that was found in the
repository was 2024-06-03.) If you discover any rendering
problems in this HTML version of the page, or you believe there
is a better or more up-to-date source for the page, or you have
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(which is not part of the original manual page), send a mail to
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liburing-2.1 February 13, 2022 io_uring_prep_write(3)
Pages that refer to this page: io_uring_prep_write_fixed(3), io_uring_register_buffers(3), io_uring_register_buffers_sparse(3), io_uring_register_buffers_tags(3), io_uring_register_buffers_update_tag(3)