Int 21 Fn 5F52  u - Lan Manager Enhanced Dos - Doswritemailslot            [N]

   AX = 5F52h
   BX = class
   CX = length of buffer
   DX = priority
   ES:DI -> DosWriteMailslot parameter structure (see #1412)
   DS:SI -> mailslot name

Return: CF clear if successful
   CF set on error
       AX = error code

See Also: AX=5F4Fh,AX=5F50h,AX=5F51h

Format of LAN Manager DosWriteMailslot parameter structure:
Offset Size    Description (Table 1412)
 00h   DWORD   timeout
 04h   DWORD   -> buffer