UDocumentation UE5.7 10.02.2026 (Source)
API documentation for Unreal Engine 5.7
FIOSFileHandle Class Reference
+ Inheritance diagram for FIOSFileHandle:

Public Member Functions

 FIOSFileHandle (int32 InFileHandle, const FString &InFilename, bool bIsForRead)
 
virtual ~FIOSFileHandle ()
 
int64 InternalRead (uint8 *Destination, int64 BytesToRead)
 
virtual bool Read (uint8 *Destination, int64 BytesToRead) override
 
virtual bool ReadAt (uint8 *Destination, int64 BytesToRead, int64 Offset) override
 
virtual bool Seek (int64 NewPosition) override
 
virtual bool SeekFromEnd (int64 NewPositionRelativeToEnd=0) override
 
virtual bool Flush (const bool bFullFlush=false) override
 
virtual bool Truncate (int64 NewSize) override
 
virtual int64 Size () override
 
virtual int64 Tell () override
 
virtual bool Write (const uint8 *Source, int64 BytesToWrite) override
 
- Public Member Functions inherited from IFileHandle
virtual ~IFileHandle ()
 
virtual void ShrinkBuffers ()
 

Constructor & Destructor Documentation

◆ FIOSFileHandle()

FIOSFileHandle::FIOSFileHandle ( int32  InFileHandle,
const FString &  InFilename,
bool  bIsForRead 
)
inline

◆ ~FIOSFileHandle()

virtual FIOSFileHandle::~FIOSFileHandle ( )
inlinevirtual

Destructor.

Member Function Documentation

◆ Flush()

virtual bool FIOSFileHandle::Flush ( const bool  bFullFlush = false)
inlineoverridevirtual

Flushes file handle to disk.

Parameters
bFullFlushtrue to flush everything about the file (including its meta-data) with a strong guarantee that it will be on disk by the time this function returns, or false to let the operating/file system have more leeway about when the data actually gets written to disk
Returns
true if operation completed successfully.

Implements IFileHandle.

◆ InternalRead()

int64 FIOSFileHandle::InternalRead ( uint8 Destination,
int64  BytesToRead 
)
inline

◆ Read()

virtual bool FIOSFileHandle::Read ( uint8 Destination,
int64  BytesToRead 
)
inlineoverridevirtual

Read bytes from the file.

Parameters
DestinationBuffer to holds the results, should be at least BytesToRead in size.
BytesToReadNumber of bytes to read into the destination.
Returns
true if the operation completed successfully. Returns false if a read is attempted while the read position is already at the end of the file.
Remarks
If BytesToRead is larger than the bytes remaining in the file from the current read position the Read() will return true if the underlying file read could read all remaining bytes.

Implements IFileHandle.

◆ ReadAt()

virtual bool FIOSFileHandle::ReadAt ( uint8 Destination,
int64  BytesToRead,
int64  Offset 
)
inlineoverridevirtual

Implements IFileHandle.

◆ Seek()

virtual bool FIOSFileHandle::Seek ( int64  NewPosition)
inlineoverridevirtual

Change the current write or read position.

Parameters
NewPositionnew write or read position
Returns
true if the operation completed successfully.

Implements IFileHandle.

◆ SeekFromEnd()

virtual bool FIOSFileHandle::SeekFromEnd ( int64  NewPositionRelativeToEnd = 0)
inlineoverridevirtual

Change the current write or read position, relative to the end of the file.

Parameters
NewPositionRelativeToEndnew write or read position, relative to the end of the file should be <=0!
Returns
true if the operation completed successfully.

Implements IFileHandle.

◆ Size()

virtual int64 FIOSFileHandle::Size ( )
inlineoverridevirtual

Return the total size of the file

Reimplemented from IFileHandle.

◆ Tell()

virtual int64 FIOSFileHandle::Tell ( )
inlineoverridevirtual

Return the current write or read position.

Implements IFileHandle.

◆ Truncate()

virtual bool FIOSFileHandle::Truncate ( int64  NewSize)
inlineoverridevirtual

Truncate the file to the given size (in bytes).

Parameters
NewSizeTruncated file size (in bytes).
Returns
true if the operation completed successfully.

Implements IFileHandle.

◆ Write()

virtual bool FIOSFileHandle::Write ( const uint8 Source,
int64  BytesToWrite 
)
inlineoverridevirtual

Write bytes to the file.

Parameters
SourceBuffer to write, should be at least BytesToWrite in size.
BytesToWriteNumber of bytes to write.
Returns
true if the operation completed successfully.

Implements IFileHandle.


The documentation for this class was generated from the following file: