off_t tmpOff;
allocBlockSize = vcb->blockSize;
- sectorSize = VCBTOHFS(vcb)->hfs_phys_block_size;
+ sectorSize = VCBTOHFS(vcb)->hfs_logical_block_size;
err = SearchExtentFile(vcb, fcb, offset, &foundKey, foundData, &foundIndex, &hint, &nextFABN);
if (err == noErr) {