Purpose: Initializes the disk in the designated or default drive to a recording format acceptable to DOS; analyzes the entire disk for any defective tracks; and prepares the disk to accept DOS files by initializing the directory, File Allocation Table, and system loader.
Format:
Type:
CAUTION
Please note that formatting destroys all data on the disk. Because of this you should be very careful before you decide to format any disk, particularly a fixed disk. If you attempt to format your fixed disk, please note that the entire contents of any previously created DO S partition,
including all subdirectories and their contents, are destroyed. If you are not certain which drive is the default drive, do NOT enter FORMAT without a drive letter. If you do not specify a drive letter, you could unintentionally destroy all of the data on whatever disk happens to be default. It's safer to specify a drive letter.
FORMAT [d: ][/S][/1 ][/8][/V][/B]
Internal External
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FORMAT Command
Remarks: You must format all new diskettes (by using either the FORMAT or DISKCOPY command) and fixed disks (through FORMAT) before they can be used by DOS.
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A fixed disk must also be formatted again if you change the size of its DOS partition through the FDISK command.
If you specify /S in the FORMAT command, the operating system files are also copied from the default drive to the new disk or diskette in the following order:
IBMBIO.COM IBMDOS.COM COMMANI1COM
If you specify /1, the target diskette is formatted for single sided use, regardless of the drive type.
If you specify /8, the target diskette is formatted for use at 8 sectors per track. FORMAT will default to 9 sectors per track usage if you do not specify /8. Note that FORMAT always creates 9 physical sectors on each diskette track, but that it instructs DOS to use only 8 sectors per track if you use the /8 parameter.
The /1 and /8 parameters are valid only for diskettes.
If you specify IV, FORMAT will prompt you for a volume label which will be written on the disk. We strongly recommend that you use the /V parameter.
This will uniquely identify each disk.
FORMAT Command
FORMAT does not allow you to enter 18 and IV at the same time. This is because DOS will not recognize a volume label on 8 sectored diskettes.
This maintains compatibility with DOS 1.10.
The volume label cannot be used in place of filenames as input to any of the DOS commands.
The volume label is for your use in keeping track of your diskettes.
The
IB
parameter causes FORMAT to create an 8 sector per track diskette with space allocated for the IBMBIO.COM and IBMDOS.COM systemmodules. It does not place the system modules or the command processor on the diskette. This parameter is used to create a diskette on which any version of DOS (1.00, 1.10,2.00, or 2.10) can be placed through that version's SYS command. If the
IB
parameter is not used, only DOS Version 2.00 or 2.10 can be placed on the diskette through the SYS command.
The IV and I S parameters cannot be used with the
IB
parameter.Notes:
1. Formatting destroys any previously existing data on the disk.
2. During the formatting process, any defective tracks are marked as reserved to prevent the tracks from being allocated to a data file.
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FORMAT Command
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3. Directory entries for IBMBIO.COM and IBMDOS.COM are marked as hidden files, and therefore, they do not appear in
any directory searches-including the DIR command.
4. FORMAT will prompt you to enter a volume label (volume identification) if you have used the /V parameter. The label can consist of from 1 to 11 characters. All characters acceptable in filenames are acceptable in the volume label. Unlike filenames, however, the volume label does not contain a period between the eighth and ninth characters.
5. FORMAT produces a status report, that indicates:
• Total disk space
• Space marked as defective
• Space currently allocated to the DOS system files (when /S is used)
• Amount of space available for your files
FORMAT Command
6. FORMAT determines the target drive type and formats the disk or diskette
accordingly. For diskettes, if the diskette can be successfully read and written on only one side, the diskette is formatted for single-sided use; it can be used in either type of drive. If the target drive is dual-sided and you do not use the /1 parameter, the diskette is formatted for dual-sided use; it will not be usable in a single-sided drive.
7. Fixed disks are already physically
formatted (proper recording format) when shipped by IBM. When formatting a fixed disk, FORMAT checks all locations within the DOS partition, but does not physically format them again.
8. If the / S parameter is used and the system has insufficient available memory for FORMAT to load all three system
modules, it will load as many modules as it can, format the target disk and write the modules that are in memory. It must then read the remaining modules from the source disk so they can be placed on the target disk. If the source diskette has been removed from the drive, an appropriate message will prompt you to reinsert it before FORMAT can continue.
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FORMAT Command
Example: By issuing the following command, the diskette in drive B is formatted and the operating system files are also copied:
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A>FORMAT B:/S/V
The system displays the following message:
Insert new diskette for drive B:
and strike any key when ready
After you insert the appropriate diskette and press any key, the system displays this message:
Formatting ...
while the diskette formatting is taking place.
Once the formatting is complete, the system displays this message:
Formatting ... Format complete System transferred
Volume label (11 character, ENTER for none)? MYDISK xxxxxx bytes total disk space
xxxxx bytes used by system
XXXXXX: Dyies avaiiabie on disk Format another (Y/N)?n
FORMAT Command
In the above example, note that MYDISK was entered as the volume label.
Enter Y to format another diskette.
Enter N to end the FORMAT program.
When you format a fixed disk, you will see the following message instead of the prompt to insert a diskette:
Press any key to begin formatUng x:
The x is replaced by the drive letter you typed. Other than this, the messages appear in the same manner.
Fixed disk formatting can take several minutes because of the large size that is allocated to DOS, so don't be alarmed if it takes some time before you are prompted for the volume label. You can tell that FORMAT is working by noting that your fixed disk drive light is on.
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