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Check an entire Power-Safe filesystem for consistency (QNX Neutrino)

Note: You must be logged in as root to run this utility.


chkqnx6s [-sv] host

Runs on:



Display header information from the superblock. The number of -v options controls which fields chkqnx6fs displays.

Note: If you specify -s, chkqnx6fs locates and verifies the active superblock, but doesn't check the filesystem itself.

Increase output verbosity. You can specify multiple -v options.
The host of the filesystem. You can specify this as a block-special device or partition (e.g. /dev/hd0t76), as a regular file, or as the root directory of a mounted fs-qnx6 filesystem (which will be resolved to the real host device).


The chkqnx6fs performs a consistency check on a Power-Safe (fs-qnx6) filesystem. The check is conducted in these passes:

  1. Locate and verify superblocks and select the newest stable one.
  2. Traverse the system inodes and bitmap files.
  3. Recursively walk the directory hierarchy from the root.

Only a stable filesystem can be checked (i.e. one that isn't going to change or be updated during the scan). A stable filesystem is one of the following:

Note: You shouldn't actually need to use chkqnx6fs in a production system (e.g. in a boot script). The design of the fs-qnx6 filesystem should (in the absence of software bugs, physical bad blocks, or malicious data modification on the raw device) make any such check unnecessary.


# chkqnx6fs -v /dev/hd0t76
** Prelude: read and verify superblocks **
** Pass 1 : verify bitmap and inodes **
** Pass 2 : verify directory hierarchy **
** Summary: 20216/8040524 blocks, 142/62816 inodes **

Exit status:

The filesystem is consistent/stable.
An error occurred checking the filesystem (descriptive messages are written to stderr).

See also:

chkfsys,, mkqnx6fs

Backing Up and Recovering Data in the Neutrino User's Guide

"Power-Safe filesystem" in the Filesystems chapter of the System Architecture guide

"Power-Safe filesystem" in the Filesystems chapter of the Neutrino User's Guide