#ifndef _NTIOAPI_H

/**
 * Instructs the file system to capture the user associated with the calling thread.
 * Subsequent calls to FltQueryVolumeInformation or ZwQueryVolumeInformationFile using the returned handle
 * use the captured user, rather than the calling user at that time, to compute available free space.
 * This applies to FileFsSizeInformation, FileFsFullSizeInformation, and FileFsFullSizeInformationEx.
 */
#define FILE_OPEN_FOR_FREE_SPACE_QUERY      0x00800000

#endif
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