Tepix on The smallest Hello World program

Comment on The smallest Hello World program

Here's a tiny DOS COM file that does it in 18 bytes:

    ;; 18 bytes
    DB 'HELLO_WOIY<$'  ; executes as machine code, returning SP to original position without overwriting return address
    
    mov  dx, si    ; mov dx,0100h MS-DOS (all versions), FreeDOS 1.0, many other DOSes
    xchg ax, bp    ; mov ah,9     MS-DOS 4.0 and later, and FreeDOS 1.0
    int  21h
    ret

(credits: https://stackoverflow.com/questions/72635031/assembly-hello-...)

rep_lodsb 1y

Well, it prints something that is the same length as the correct message at least.

musicale 1y

COM files for CP/M and DOS really are a no-nonsense executable format.

I'm a bit disappointed that Linux (or BSD, macOS, etc.) doesn't support them (or similar) out of the box, though Windows will sort of run them via ntvdm.

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