TITLE Concat   (Concat.asm)

; Program Description: This program uses a procedure to take a source
;                      string and add it to the end of the target string
; Author: Brian Brindle


INCLUDE Irvine32.inc

Str_concat PROTO,
	target:PTR BYTE,
	source:PTR BYTE

.data
targetStr BYTE "ABCDE",10 DUP(0)
sourceStr BYTE "FGH",0


.code
main PROC
	call Clrscr
	Invoke Str_concat, ADDR targetStr, ADDR SourceStr

	mov edx, OFFSET targetStr
	call WriteString
	call Crlf

	exit
main ENDP

;---------------------------------------------------------
;This function will concatenate a source string to the end
;of a target string
;Receives: the address of the source and target strings
;Returns: nothing
;---------------------------------------------------------
Str_concat PROC USES eax ebx ecx esi edi,
	target:PTR BYTE,
	source:PTR BYTE

	mov eax, 5                ; the size of target string
	mov ecx, SIZEOF source    ; ecx determines number of loops
	mov esi, source
	mov edi, target

L1:
	add edi, eax              ; end of target string
	mov ebx, [esi]
	mov [edi], ebx            ; copy Byte to the end of target

	add eax, 1
	add esi, 1
	loop L1

	ret
Str_concat ENDP

END main