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I just encountered this problem

### Overview of HPFS
The HPFS file system was first introduced with OS/2 1.2, aiming to enhance the ability to access larger hard disks emerging in the market at that time. Additionally, a new file system was needed then that could expand the naming system, organization, and security to meet the growing demands of the network server market. HPFS retained the directory organization of FAT while adding automatic directory sorting based on file names. File names were extended to up to 254 double-byte characters. HPFS also allowed files to be composed of "data" and special attributes, thereby increasing flexibility in supporting other naming rules and security. Moreover, the allocation unit was changed from clusters to physical sectors (512 bytes), which reduced the waste of disk space.

Under HPFS, directory entries contain more information than under FAT. As for attribute files, they also include information about modification, creation, access dates, and times. Under HPFS, directory entries do not point to the first cluster of a file but to an FNODE. An FNODE can contain the file's data, pointers to the file's data, or other structures that ultimately point to the file's data.

HPFS attempts to allocate a file in as many consecutive sectors as possible. This is done to improve the speed of sequential file processing.

HPFS organizes a drive into a series of 8 MB bands, and files are included in one of these bands whenever possible. Between bands are 2K allocation bitmaps to track which sectors within a band are allocated and which are not. Banding can improve performance because the drive head does not have to return to the logical top of the disk (usually cylinder 0), but only needs to return to the nearest band allocation bitmap to determine where the file is stored.

In addition, HPFS also includes two unique special data objects

Learning

The partition flags of HPFS and NTFS are both 07H. It is best not to mix them, otherwise problems are very likely to occur.

Originally posted by netwinxp at 2009-5-4 09:02 PM:
Both HPFS and NTFS use partition flag 07H. It's best not to mix them, otherwise problems are likely to occur.

HPFS and NTFS indeed both use 07, but Windows' NTFS driver can well distinguish between the two and won't make a mistake. Because the code in Windows NT from the very beginning included code to identify HPFS partitions, and it can distinguish HPFS and NTFS from other information of the file system.

I tried it before. The chkdsk and convert commands in XP can recognize HPFS partitions. When trying to operate on an HPFS partition, it will prompt that this version of chkdsk/convert doesn't support HPFS partitions, while these commands in Windows NT 3.x can directly operate on HPFS partitions.

[ Last edited by fujianabc on 2009-5-5 at 05:03 ]

Waited all day and need this thing

Let's see if it's really true

After the shared folder of the VMware virtual machine is mapped to a hard disk, the format of the hard disk is hffs

Haha, IBM was really messed up by Microsoft and also Intel...

Thanks for sharing

Apple, IBM, and Microsoft were previously partners, and Windows NT maintained most compatibility with OS/2.