QNX 4 filesystem

The QNX 4 filesystem (fs-qnx4.so) is a high-performance filesystem that shares the same on-disk structure as in the QNX 4 RTOS.

The QNX 4 filesystem implements an extremely robust design, utilizing an extent-based, bitmap allocation scheme with fingerprint control structures to safeguard against data loss and to provide easy recovery. Features include:

Note: In QNX Neutrino 6.2.1 and later, the 48-character filename limit has increased to 505 characters via a backwards-compatible extension. The same on-disk format is retained, but new systems will see the longer name, while old ones will see a truncated 48-character name.

For more information, see "QNX 4 filesystem" in the Working with Filesystems chapter of the QNX Neutrino User's Guide.