IAsyncReadFileHandle::ReadRequest

Submit an async request and/or wait for an async request

Windows
MacOS
Linux

Override Hierarchy

IAsyncReadFileHandle::ReadRequest()

FLoggingAsyncReadFileHandle::ReadRequest()

References

Module

Core

Header

/Engine/Source/Runtime/Core/Public/Async/AsyncFileHandle.h

Include

#include "Async/AsyncFileHandle.h"

Syntax

IAsyncReadRequest * ReadRequest
(
    int64 Offset,
    int64 BytesToRead,
    EAsyncIOPriorityAndFlags PriorityAndFlags,
    FAsyncFileCallBack * CompleteCallback,
    uint8 * UserSuppliedMemory
)

Remarks

Submit an async request and/or wait for an async request

Returns

A request for the read. This is owned by the caller and must be deleted by the caller.

Parameters

Parameter

Description

Offset

Offset into the file to start reading.

BytesToRead

number of bytes to read. If this request is AIOP_Preache, the size can be anything, even MAX_int64, otherwise the size and offset must be fully contained in the file.

PriorityAndFlags

Priority and flags of the request. If this includes AIOP_FLAG_PRECACHE, then memory will never be returned. The request should always be canceled and waited for, even for a precache request.

CompleteCallback

Called from an arbitrary thread when the request is complete. Can be nullptr, if non-null, must remain valid until it is called. It will always be called.

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