INT 1A - SNAP.EXE 3.2+ - "SNAP_SETANCHOR"
AX = 7002h
STACK:  WORD    anchor number (0000h-0009h)
WORD    new value for the anchor
Return: AX = status
0000h successful
FFFFh failed (top word on stack not in range 00h-09h)
STACK unchanged

See also: 1A7101

1A7002 - SNAP.EXE 3.2+ - "SNAP_SETANCHOR"