MZ is back!HEADmain

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diff --git a/v4.0/src/MAPPER/F_CLOSE.ASM b/v4.0/src/MAPPER/F_CLOSE.ASM
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+page 80,132
+
+title CP/DOS  DosFindClose  mapper
+
+        include find.inc
+
+
+FindSegment     segment word public 'find'
+
+; We will use the offset into the segment 'FindSegment' as the handle that we
+;  return and use in subsequent FindNext and FindClose calls.  The data that is
+;  in the word is the offset into the 'FindSegment' to the DTA that we should
+;  use.
+                extrn   FindDTAs:word
+                extrn   FindHandles:word
+
+FindSegment     ends
+
+
+; ************************************************************************* *
+; *
+; *      MODULE: DosFindClose
+; *
+; *      FUNCTION:  Close Find Handle
+; *
+; *      FUNCTION: This module closes the directory handle used by CP/DOS
+; *                in a find first/find next search.  Since PC/DOS does not
+; *                use directory handles it will simply return to the caller
+; *                removing the parameters passed on the stack.
+; *
+; *      CALLING SEQUENCE:
+; *
+; *                PUSH  WORD  DirHandle   ; Directory search handle
+; *                CALL DosFindClose
+; *
+; *
+; *      RETURN SEQUENCE:
+; *
+; *                IF ERROR (AX not = 0)
+; *
+; *                   AX = Error Code:
+; *
+; *
+; *      MODULES CALLED:  None
+; *
+; *************************************************************************
+
+        public  DosFindClose
+        .sall
+        .xlist
+        include macros.inc
+        .list
+
+str     struc
+old_bp    dw      ?
+return    dd      ?
+DirHandle dw      ?           ; dirctory search handle
+str     ends
+
+
+dosxxx  segment byte public 'dos'
+        assume  cs:dosxxx,ds:nothing,es:nothing,ss:nothing
+
+DosFindClose  proc   far
+        Enter   DosFindClose               ; push registers
+
+        mov     ax,seg FindSegment         ; get address to our data
+        mov     ds,ax
+        assume  ds:FindSegment
+
+; Close the handle
+
+; The 'DirHandle' that the mapper returns from FindFirst, is the offset into
+; 'FindSegment' of the pointer to the DTA for that Handle.  The 08000h bit
+; of the pointer is used to indicate that the handle is open.  Reset the bit.
+
+; Special Logic to handle DirHandle = 1
+
+        mov     si,[bp].DirHandle          ; get directory hanlde
+        cmp     si,1                       ; handle = 1??
+        jne     CheckForClose              ; branch if not
+
+        mov     si,offset FindSegment:FindHandles
+
+CheckForClose:
+        test    ds:[si],OpenedHandle       ; handle is open ??
+        jnz     OkToClose                  ; go and close if it is open
+
+        mov     ax,6                       ; else load error code
+        jmp     ErrorExit                  ; return
+
+OkToClose:
+        and     ds:[si],not OpenedHandle   ; set close flag
+        xor     ax,ax                      ; set good return code
+
+ErrorExit:
+        mexit                              ; pop registers
+        ret     size str - 6               ; return
+
+DosFindClose endp
+
+dosxxx  ends
+
+        end