QNX 4 filesystem

The limits for QNX 4 filesystems include:

Filename length
48 bytes, or 505 if .longfilenames exists before mounting; see "Filenames" in the description of the QNX 4 filesystem in Working with Filesystems.
Pathname length
1024 bytes
File size
2 GB − 1
Directory size
No practical limit, although the files that the directory uses to manage its contents are limited to 2 GB − 1 bytes, which works out to approximately 33 million files in a single directory. You wouldn't want to do that, though, as directory scans are linear: they'd be very slow.
Filesystem size
2 GB × 512; limited by the disk driver
Disk size
264 bytes; limited by the disk driver
Maximum user and group ID for chgrp or chown
65534