windows - Determining volume cluster size without using GetDiskFreeSpace -


i'd programmatically determine cluster (a.k.a. allocation unit) size of volume (a.k.a. file system) mounted on windows system. various reasons, i'd find solution not use getdiskfreespace().

are there fsctl_xxx or ioctl_xxx requests can used purpose?

you can use deviceiocontrol ioctl_storage_query_property. on input, set propertyid in storage_property_query structure storageaccessalignmentproperty.

that storage_access_alignment_descriptor, contains members both bytesperlogicalsector , bytesperphysicalsector. linked reference page includes demo code retrieve , display logical/physical sector sizes device.


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