Int 2F Fn 1400  C - Nlsfunc.com - Installation Check                       [U]

   AX = 1400h

Return: AL = 00h not installed, OK to install
        01h not installed, not OK
        FFh installed

Notes: this function is called by the DOS v3.3+ kernel
   supported by OS/2 v1.3+ compatibility box, which always returns AL=FFh
   supported by DR DOS 5.0
   documented for MS-DOS 5+, but undocumented in prior versions

See Also: AX=1401h"NLSFUNC",AX=1402h"NLSFUNC"