N: Device Filename Size Limitations

Not all DOS are Equal

CIO does not care about the size of a device specification; only that there is a buffer large enough to hold the device-spec, and that its length is properly passed to the CIOV call.

The various file management systems (FMS) present in different disk operating systems (DOS) are another matter, entirely. These differing FMSes impose their own unique limitations, and this discrepancy will become very important as a mapping scheme is implemented for file-level operations in the N: device.

Legal Filename Length comparison

DOS	Length
DOS 1.0	8.3 1
DOS 2.0	8.3 1
DOS 3.0	8.3 2
DOS 4.0	125
MyDOS	256
OS/A+	23
DOS XL	23
XDOS	45

Notes

1. The DUP throws a FILENAME TOO LONG error if this limit is breached.
2. A combination of explicit input length limiting and over-eager pre-pending of D1: before N: for any KCP operations make this DOS unsuitable for N: usage in the utility package. An external utility will be needed.