I have a task to print a buffer and some other text into a file and when I use this code I get a wrong answer. Outputing a buffer is OK, it prints perfectly, but when I try to print text, declared in data, non-senses start happening. For example, when I try to print "Hello (letters )", it gives me this "Hello (9 spaces)(letters$)$". When I write 3 different procedures for each string, it prints correctly. Maybe you can help me find the problem, guys?
model small
BufSize EQU 60
.stack 100h
.data
rez db "rez.txt",
Buf db BufSize dup (?)
handle dw ?
Letters db 0
brackets1 db " (letters$"
brackets2 db ")$"
.code
start:
MOV ax, @data
MOV ds, ax
MOV ah, 3Ch
MOV cx, 0
MOV dx, offset rez
INT 21h ;results file is created and opened
MOV handle, ax
MOV cx, 5 ;5 bytes ("Hello")
ADD cx,10 ;10 bytes from "(letters " and ")"
MOV bx, handle
CALL Write
MOV ah, 3Eh
MOV bx, handle
INT 21h ;close file
MOV ah, 4Ch
MOV al, 0
INT 21h
PROC Write
PUSH dx
MOV ah, 40h
MOV dx, offset Buf
INT 21h ;Write to file
MOV ah,40h
MOV dx,offset brackets1
INT 21h
MOV ah,40h
MOV dx,offset brackets2
INT 21h
POP dx
RET
RasykBuf ENDP
END start
I've added some omitted instruction and new comments; there was one compiling error that I've corrected: RasycBuf ENDP (isn't Write the name of the PROCedure ?). Whenever you do an I/O operation, you must check if it is successfully done, otherwise the next I/O's operation can generate a RUN-TIME's ERROR.
I've successfully compiled this source code.
However I don't know what you want it does, because the program, as said by another user, is incomplete.
model small
BufSize EQU 60
.stack 100h
.data
rez db "rez.txt", 0 ; NULL TERMINATOR WAS OMIT.
Buf db BufSize dup (32) ; CHARACTERS WITHOUT A PURPOSE (SPACES).
;handle dw ? ; NOT NEEDED.
;Letters db 0 ; NOT USED.
brackets1 db " (letters$"
brackets2 db ")$"
.code
start:
MOV ax, @data
MOV ds, ax
MOV ah, 3Ch
MOV cx, 0
MOV dx, offset rez
; AH -> 3CH, CREATE A FILE WITH HANDLE.
; CX -> Attribute for file:
; Bit0: read-only.
; Bit1: hidden.
; Bit2: system.
; Bit3: volume-label.
; Bit4: directory.
; Bit5: archive.
; Bit6: UNKNOWN.
; Bit7: shareable.
; DS:DX -> ASCIZ file-name (with optional drive and path).
; OUTPUT -> FCarry=1: ERROR, AX= error-code;
; FCarry=0: SUCCESSFULL, AX= file-handle.
INT 21h ; Results file is created and opened.
JB openfailed ; If error, exit.
;MOV handle, ax ; Not needed.
;MOV cx, 5 ; 5 bytes ("Hello")
;ADD cx, 10 ; 10 bytes from "(letters " and ")"
MOV bx, ax ; Copy file-handle into BX's reg.
CALL Write
MOV ah, 3Eh
;MOV bx, handle ; BX's reg. already contains handle.
; AH -> 3EH, CLOSE A FILE WITH HANDLE.
; BX -> File-handle
; OUTPUT -> FCarry=1: ERROR, AX= error-code;
; FCarry=0: SUCCESSFULL.
INT 21h ; Close file
openfailed:
MOV ah, 4Ch
MOV al, 0
; AH -> 4CH, QUIT WITH EXIT CODE (EXIT).
; AL -> EXIT CODE.
INT 21h
Write:
; I suppose that you want to write the content of the buffer (Buf),
; followed by brackets1 and brackets2 strings.
; NOTE: Buf CONTAINS ONLY CHARACTERS WITHOUT A PURPOSE !
;PUSH dx ; Because DX's reg. is only used here, don't need to PUSH/POP it
MOV ah, 40h
MOV cx, BufSize ; Size of Buf
MOV dx, offset Buf
; AH -> 40H, WRITE TO FILE WITH HANDLE
; BX -> Handle
; CX -> Buffer's size
; DS:DX -> Buffer
; OUTPUT -> FCarry=1: ERROR, AX= error-code;
; FCarry=0: SUCCESSFULL, AX= num. of byte written.
INT 21h ; Write to file
JB error ; If error, return
MOV ah, 40h
MOV cx, 10 ; Size of brackets1's string
MOV dx, offset brackets1
; AH -> 40H, WRITE TO FILE WITH HANDLE
; BX -> Handle
; CX -> Buffer's size
; DS:DX -> Buffer
; OUTPUT -> FCarry=1: ERROR, AX= error-code;
; FCarry=0: SUCCESSFULL, AX= num. of byte written.
INT 21h
JB error ; If error, return
MOV ah, 40h
MOV cx, 2 ; Size of brackets2's string
MOV dx, offset brackets2
; AH -> 40H, WRITE TO FILE WITH HANDLE
; BX -> Handle
; CX -> Buffer's size
; DS:DX -> Buffer
; OUTPUT -> FCarry=1: ERROR, AX= error-code;
; FCarry=0: SUCCESSFULL, AX= num. of byte written.
INT 21h
error:
;POP dx ; Because DX's reg. is only used here, don't need to PUSH/POP it
RET
END start