BASIC-DOS

CHKDSK

CHKDSK [drive:] [/V]

Checks the FAT and directories of drive (or the current drive): every file’s and directory’s cluster chain is followed, and any problems are reported. Then CHKDSK reports the volume label (with its date and time) and the space on the drive: the total, the bad sectors, the hidden files, directories, and user files (each in whole clusters), the lost clusters, and the space available. Lines that would report nothing (eg, bad sectors, on most disks) aren’t displayed.

/V lists the name of every file and directory as it’s checked.

CHKDSK A:

Volume BD-D40      created 10-23-2026 12:08a

      362496 bytes total disk space
       46080 bytes in 2 hidden files
        3072 bytes in 3 directories
      214016 bytes in 53 user files
       99328 bytes available on disk

Unlike PC DOS, CHKDSK only reports problems (there’s no /F to fix them), and it doesn’t report memory (see MEM).

Problems

CHKDSK can report these problems with a drive, and if it reports any of them, it follows them with Errors found (CHKDSK reports them, but can't fix them):

• file is cross-linked on cluster n: the chain shares a cluster with another chain
• file allocation error (size n but n clusters): the chain doesn’t match the file’s size
• file has an invalid cluster n: the chain contains a cluster that isn’t on the drive
• n lost clusters found in n chains: these clusters are in use, but in no file’s chain

Limits and Other Messages

CHKDSK reads the volume directly (see OPEN), so it can’t check directories beyond the first 14Mb of a volume, which it reports (path is beyond the first 14Mb (not checked)). It can also keep track of only so many subdirectories, and reports any others (path not checked (too many subdirectories)). The clusters of a directory that wasn’t checked would look lost, so in either case, CHKDSK displays Not all directories were checked, so lost clusters aren't reported, and doesn’t report any.

CHKDSK can’t check a drive if it finds one of these problems:

• Drive not ready
• Invalid drive
• Drive drive doesn't have a FAT volume
• Unable to check drive drive (error n), for any other error

Any argument other than a drive and /V, or more than one drive, displays Syntax error.

ERRORLEVEL is set to 0 if CHKDSK checked the entire volume and found no problems, and otherwise to 1.

Source: CHKDSK.BAS

« ATTRIBCOMMAND.COM »