static async Task Core(string path, byte[] bytes, CancellationToken cancellationToken)
{
#if MS_IO_REDIST
using FileStream fs = new FileStream(path, FileMode.Create, FileAccess.Write, FileShare.Read, 1, FileOptions.Asynchronous | FileOptions.SequentialScan);
await fs.WriteAsync(bytes, 0, bytes.Length, cancellationToken).ConfigureAwait(false);
#else
using SafeFileHandle sfh = OpenHandle(path, FileMode.Create, FileAccess.Write, FileShare.Read, FileOptions.Asynchronous | FileOptions.SequentialScan);
await RandomAccess.WriteAtOffsetAsync(sfh, bytes, 0, cancellationToken).ConfigureAwait(false);
#endif
}
public override ValueTask WriteAsync(ReadOnlyMemory <byte> source, CancellationToken cancellationToken)
{
if (!CanWrite)
{
ThrowHelper.ThrowNotSupportedException_UnwritableStream();
}
long filePositionBefore = -1;
if (CanSeek)
{
filePositionBefore = _filePosition;
_filePosition += source.Length;
}
return(RandomAccess.WriteAtOffsetAsync(_fileHandle, source, filePositionBefore, cancellationToken));
}