1 files changed, 63 insertions, 0 deletions

diff --git a/v4.0/src/MAPPER/READ.ASM b/v4.0/src/MAPPER/READ.ASM
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+++ b/v4.0/src/MAPPER/READ.ASM
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+page 80,132
+
+title CP/DOS DosRead mapper   * * *
+
+dosxxx  segment byte public 'dos'
+        assume  cs:dosxxx,ds:nothing,es:nothing,ss:nothing
+
+;**********************************************************************
+;*
+;*   MODULE:   dosreade
+;*
+;*   FUNCTION: Read a specified number of bytes from the file
+;*
+;*   CALLING SEQUENCE:
+;*
+;*       push      word     file handle
+;*       push@     other    buffer area
+;*       push      word     buffer length
+;*       push@     word     bytes read
+;*       call      dosread
+;*
+;*   MODULES CALLED:  PC-DOS Int 21h, ah=3fh,
+;*
+;*********************************************************************
+
+            public   dosread
+            .sall
+            .xlist
+            include  macros.inc
+            .list
+
+str         struc
+old_bp      dw       ?
+return      dd       ?
+Written     dd       ?       ; number of bytes actually read
+Bufflng     dw       ?       ; number of bytes to be read
+Buffer      dd       ?       ; read buffer
+Handle      dw       ?       ; handle
+str         ends
+
+dosread     proc     far
+            Enter    Dosread           ; save registers
+
+            mov      bx,[bp].handle    ; fill registers for
+            lds      dx,[bp].buffer    ; function call
+            mov      cx,[bp].bufflng   ; number of bytes to read
+
+            mov      ah,3fh            ; load opcode
+            int      21h               ; read from file
+            jc       exit              ; jump if error
+
+            lds      si,[bp].written   ; else, set return data area
+            mov      word ptr [si],ax  ; save number of bytes read
+            sub      ax,ax             ; set good return code
+
+exit:       mexit                      ; pop registers
+            ret      size str - 6      ; rturn
+
+dosread     endp
+
+dosxxx      ends
+
+            end