Int 2F Fn 4810  - Dos 5+ Doskey, Pced V2.1 - Read Input Line From Console  [K]

   AX = 4810h
   DS:DX -> line buffer (see #1033 at INT 21/AH=0Ah)

Return: AX = 0000h if successful

Notes: the first byte (length) of the buffer MUST be 80h, or MS-DOS's DOSKEY
     chains to the previous handler; PCED and Novell DOS allow sizes
     other than 80h
   if the user's input is a macro name, no text is placed in the buffer
     even though AX=0000h on return; the program must immediately issue
     this call again to retrieve the expansion of the macro.  Similarly,
     if the user enters a special parameter such as $*, this call must
     be repeated to retrieve the expansion; on the second call, DOSKEY
     overwrites the macro name on the screen with its expansion.
   unlike DOSKEY, PCED expands all macros on the first call, so it is
     not necessary to make two calls; since the buffer is not empty on
     return, DOSKEY-aware programs will not make the second call
   DOSKEY chains if AL is not 00h or 10h on entry
   this function is supported by Novell DOS 7 DOSKEY

See Also: AX=4800h,INT 21/AH=0Ah