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Q38113: CHKDSK and File Allocation Adjustments

Article: Q38113
Product(s): Microsoft Disk Operating System
Version(s): MS-DOS:3.x,4.x,5.x,6.0,6.2,6.21,6.22
Operating System(s): 
Keyword(s): 
Last Modified: 17-DEC-2000

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The information in this article applies to:

- Microsoft MS-DOS operating system versions 3.1, 3.2, 3.21, 3.3, 3.3a, 4.0, 4.01, 5.0, 5.0a, 6.0, 6.2, 6.21, 6.22 
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SUMMARY
=======

CHKDSK uses the File Allocation Table (FAT) to determine the condition of both
of the following:

- Disks as a whole

- Files

MORE INFORMATION
================

The size of every file is stored in the file's directory entry. The chain size
of any file is defined to be the number of clusters on the disk that it occupies
multiplied by the number of bytes in each cluster. CHKDSK compares the two
reported sizes to see if the directory entry and the FAT are comparable. CHKDSK
displays the error message "Allocation error, size adjusted" if the sizes are
incorrect.

The error is displayed when either of the following conditions is met:

- The file size located in the directory entry is larger than the chain size.

-or-

- The chain size is more than one cluster size larger than the reported file
  size.

To adjust the size of the file, CHKDSK changes the directory entry to match the
chain size.

Additional query words: 6.22 3.20 3.21 3.30 3.30a 4.00 5.00 5.00a 6.00 6.20

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Keywords          :  
Technology        : kbMSDOSSearch kbMSDOS321 kbMSDOS400 kbMSDOS320 kbMSDOS330a kbMSDOS621 kbMSDOS622 kbMSDOS620 kbMSDOS600 kbMSDOS310 kbMSDOS500 kbMSDOS330 kbMSDOS401 kbMSDOS500a
Version           : MS-DOS:3.x,4.x,5.x,6.0,6.2,6.21,6.22

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