Note: This is the June 17, 2006 capture of from the Wayback Machine. This was uploaded to the reloaded ISLESV.NET on June 22, 2023.

; COMARGS.ASM: Returns first command-line argument passed to program.
; Start with a dash, only 13 chars.
; This file Copyright (C) 2004-2005 by Vincent "Bentong" S. Isles

        .MODEL  SMALL
        ORG     100H
MPARA   DB      'Passed parameter is $'
NOPARA  DB      'No parameters.$'
EMSG    DB      'Usage: PARA -parameter$'

        MOV     BL,ES:[80H]             ; ES,CS,DS, whatever: COM only takes
                                        ; one segment. We'll use ES cOZ for
                                        ; EXE it points to PSP starting address
        CMP     BL,0                    ; are there any characters?
        JZ      NO_PARAM                ; we have no characters

        MOV     CL,2                    ; we'll look for two '-'
        MOV     SI,81H                  ; point SI to start of CTL

SKIP_BLANKS:                            ; start of process
        MOV     BL,ES:[SI]              ; get a character
        INC     SI                      ; increment first
        CMP     BL,20H                  ; blank char, get another
        JZ      SKIP_BLANKS
        CMP     BL,0DH                  ; carriage return
        JZ      NO_PARAM                ; no parameters
        CMP     BL,'-'                  ; daz wat we looking 4
        JZ      GET_PARA
        LEA     DX,EMSG
        MOV     AH,9
        INT     21H
        JMP     GOODBYE

        MOV    [SI+12],' $'             ; str end char
                                        ; just to make dear TASM happy

        LEA     DX,MPARA                ; "Passed parameter is "
        MOV     AH,9
        INT     21H

        MOV     DX,SI                   ; beginning of first para
        MOV     AH,9
        INT     21H
        JMP     GOODBYE                 ; let's get out

NO_PARAM:                               ; we got no parameter
        LEA     DX,NOPARA               ; no parameter string
        MOV     AH,9                    ; disp str
        INT     21H

GOODBYE:                                ; let's get out
        INT     20H
        END     ENTRY