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;
page 60,132
;
title CP/DOS DOSExecPrg mapper
buffer segment word public 'buffer'
public DosExecPgmCalled
DosExecPgmCalled db 0 ;????????????
public DosExecPgmReturnCode
DosExecPgmReturnCode dw 0
DosExecParameterBlock label word
EnvironmentSegment dw 0
ArgumentPointer dd 0
Default_5C_FCB dd 0
Default_6C_FCB dd 0
buffer ends
dosxxx segment byte public 'dos'
assume cs:dosxxx,ds:nothing,es:nothing,ss:nothing
;
; ************************************************************************* *
; *
; * MODULE: DosExecPgm
; *
; * FUNCTION: Allows a program to execute another program
; *
; * CALLING SEQUENCE:
; *
; * push Asyncindic ; execute asynchronously
; * push TraceIndic ; trace process
; * push Argpointer ; address of arguments string
; * push Envpointer ; address of environment string
; * push Processid ; address to put process id
; * push PgmPointer ; address of program filename
; * call dosexecpgm
; *
; * RETURN SEQUENCE: AX = error code
; *
; *
; *
; * MODULES CALLED: INT 21H function 4BH and 4DH
; *
; *
; *
; *************************************************************************
public dosexecpgm
.sall
.xlist
include macros.inc
.list
inv_parm equ 0002
not_suf_mem equ 0004
str struc
old_bp dw ?
return dd ?
Pgmpointer dd ? ; address of program file name
Processid dd ? ; this is used when only sync exec
EnvPointer dd ? ; address of environment string
ArgPointer dd ? ; address of argument string
Traceindic dw ? ; ignored, what is a trace process?
Asyncindic dw ? ; ignored, PC-DOS always waits!
str ends
dosexecpgm proc far ; push registers
Enter dosexecpgm
mov ax,seg buffer ; setup buffer segment
mov ds,ax ; and copy info into
assume ds:buffer ; data buffer
mov ax,word ptr [bp+2].EnvPointer ; seg portion only for pc-dos
mov EnvironmentSegment,ax ; copy environment string
les di,[bp].ArgPointer
mov word ptr ArgumentPointer+0,di ; copy argument string
mov word ptr ArgumentPointer+2,es
xor ax,ax
mov word ptr Default_5C_FCB+0,ax ; setup defaults
mov word ptr Default_5C_FCB+2,ax
mov word ptr Default_6C_FCB+0,ax
mov word ptr Default_6C_FCB+2,ax
mov bx,ds
mov es,bx
mov bx,offset buffer:DosExecParameterBlock
lds dx,[bp].PgmPointer ; setup program name
mov ax,4b00h
int 21h ; exec program and
jc ErrorExit ; check for error
mov ah,4dh
int 21h ; get return code of program
jc ErrorExit ; just executed and jump if
; error
mov bx,seg buffer
mov ds,bx
mov DosExecPgmReturnCode,ax ; else, save return code
xor ax,ax ; set no error code
ErrorExit:
Mexit ; pop registers
ret size str - 6 ; return
dosexecpgm endp
dosxxx ends
end
|
