[mrfinn]

These challenges are funny - they remind me of the old days. Back in the DOS/Windows days, we used to have the .com format, which was perfect for tiny programs. One could even write a program of less than 10 bytes that could actually do something!

We've come a long way since then, and is like, at some point, nobody cared about optimizing executable size anymore

[secondcoming]

People in the embedded space care. Symbian OS was compiled for small size, only certain parts were allowed use O3, such as the jpeg decoder.

[theandrewbailey]

Some people care about executable size, (mostly) everyone else ships Electron apps.

[ramon156]

Tell it to my boss, he wants his app last week.

[hinkley]

I learned to write COM programs at some point but quickly unlearned it. There were some spots where you can use them and not .bat files, but outside of that it’s a lot.

[smokel]

  debug
  -a 100
  178A:0100 int 19
  178A:0102
  -r cx
  CX 0000
  :2
  -n reboot.com
  -w
  Writing 00002 bytes
  -q

[dim13]

Some more:

Quick'n'dirty:

    .model small
    .code
     org 100h
    start:
     int 19h                 ; Bootstrap loader
    end start

More "correct":

    .model small
    .code
     org 100h
    start:
     db 0EAh                 ; Jump to Power On Self Test - Cold Boot
     dw 0,0FFFFh
    end start

Even more "correct":

    .model small
    .code
     org 100h
    start:
     mov ah,0Dh
     int 21h                 ; DOS Services  ah=function 0Dh
                             ;  flush disk buffers to disk
     sti                     ; Enable interrupts
     hlt                     ; Halt processor
     mov al,0FEh
     out 64h,al              ; port 64h, kybd cntrlr functn
                             ;  al = 0FEh, pulse CPU reset
    end start

[mrfinn]

Great example, a two bytes reboot utility. From the times when we could turn off the computer with a push of a button without fearing a global catastrophe...

[xpasky]

JMP FFFF:0000

[mrfinn]

INT 13h... uff chills