| .\" Copyright (C) 2021 Stefan Roesch <shr@fb.com> |
| .\" |
| .\" SPDX-License-Identifier: LGPL-2.0-or-later |
| .\" |
| .TH io_uring_cqe_get_data 3 "November 15, 2021" "liburing-2.1" "liburing Manual" |
| .SH NAME |
| io_uring_cqe_get_data \- get user data for completion event |
| .SH SYNOPSIS |
| .nf |
| .B #include <liburing.h> |
| .PP |
| .BI "void *io_uring_cqe_get_data(struct io_uring_cqe *" cqe ");" |
| .BI " |
| .BI "__u64 io_uring_cqe_get_data64(struct io_uring_cqe *" cqe ");" |
| .fi |
| .SH DESCRIPTION |
| .PP |
| The |
| .BR io_uring_cqe_get_data (3) |
| function returns the user_data with the completion queue entry |
| .IR cqe |
| as a data pointer. |
| |
| The |
| .BR io_uring_cqe_get_data64 (3) |
| function returns the user_data with the completion queue entry |
| .IR cqe |
| as a 64-bit data value. |
| |
| After the caller has received a completion queue entry (CQE) with |
| .BR io_uring_wait_cqe (3), |
| the application can call |
| .BR io_uring_cqe_get_data (3) |
| or |
| .BR io_uring_cqe_get_data64 (3) |
| function to retrieve the |
| .I user_data |
| value. This requires that |
| .I user_data |
| has been set earlier with the function |
| .BR io_uring_sqe_set_data (3) |
| or |
| .BR io_uring_sqe_set_data64 (3). |
| |
| .SH RETURN VALUE |
| If the |
| .I user_data |
| value has been set before submitting the request, it will be returned. |
| Otherwise the functions returns NULL. |
| .SH SEE ALSO |
| .BR io_uring_get_sqe (3), |
| .BR io_uring_sqe_set_data (3), |
| .BR io_uring_sqe_submit (3) |
