THIS PROGRAM IS A DOS APPLICATION THAT WILL NOT FUNCTION IN WINDOWS
The PART DOS utility uses the same mechanisms as Partition Magic and GDISK (Ghost) to Hide and Unhide partitions. These utilities typically add 10 hex to the DOS partition type code. Since all the DOS partition type codes are less than 0F hex, this will always result in a type code between 10 hex and 1F hex. Since no valid partition type codes currently exist between 10 hex and 1F hex (DOS or otherwise), it can be assumed that any partition with such a type code is a hidden partition. DOS will simply ignore partitions with type codes between 10 hex and 1F hex (since those types are undefined) and no drive letter will be assigned. In order to return such a hidden partition to service, it is a simple matter to subtract 10 hex from the type code and reboot.
The PART utility may be used to switch between multiple bootable primary partitions. Although FDISK will not create multiple primary partitions, MS-DOS has no problem supporting multiple DOS primaries without the addition of any other special software. (Other utilities, such as the GDISK utility provided with Symantec's GHOST, can be used to create multiple primary DOS partitions).
It is possible to automatically boot into a standalone DOS partition when shutting down Windows 95 or 98 by making use of a special shutdown file. Windows will automatically execute the contents of the C:\WINDOWS\DOSSTART.BAT file after the "Restart in MS-DOS Mode" option is selected from the "Shut Down" dialog box. Normally, the GUI is unloaded and then commands in DOSSTART.BAT are executed to load support for Mice and other devices. By replacing the contents of DOSSTART.BAT with a line such as "PART BOOT 2", you can effectively cause the bootable partition to be reset and the system rebooted into a different OS (i.e. DOS).
Tips on creating a multi-boot Windows/DOS system: In order for a partition to be bootable, it must begin within the first 2 Gb of a disk drive. Understanding this fact, it is often desirable to create a small (100-200 Mb) DOS bootable primary partition (FAT 16) at the beginning of the disk, and then create a second Windows 95/98 primary partition (FAT 16 or 32) immediately following it. This type of configuration would result in the DOS partition to be number "1" and the Windows partition to be number "2". You could then use the previously mentioned technique with "PART BOOT 1" in the DOSSTART.BAT file to automatically reboot into a pure DOS partition when "Restarting in MS-DOS Mode". Similarly, a file named "WIN98.BAT" could be created in the DOS path in the DOS environment which contains "PART BOOT 2" to automatically reboot in Windows 98.
Download PART Documentation for Additional Information (PDF)