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emanuele-em
301 bytes! The base64 one-liner install is a nice flex. Accepting an infinite loop when energy_full doesn't exist is peak code golf, perfectly reasonable when every byte counts. Is there a writeup on the assembly somewhere?
zahlman
The xz step doesn't seem to be doing very much, though. It seems the decoded data is currently 278 bytes versus a 298-byte decompressed result.
sjdv1982
Haha this is great!

What about adding a Make rule to auto-generate the one-liner install from the binary?

billforsternz
I would prefer avoiding the infinite loop and printing a message to help the user understand what went wrong. I'm sure you could do that with an extra 100 bytes or so. Just my opinion of course.
captn3m0
I have a use for this: A somewhat portable one-liner to go in my waybar/sway/i3 configs!
vparseval
Love it! It's entirely inapplicable and useless to me but it embodies the spirit of Show HN and what the spirit of programming in the 80s and 90s was.
Eric_Xua
Love this kind of tiny, over‑engineered hack—totally impractical, but pure Show HN energy.
userbinator
It doesn't even look like particularly optimised Asm (could immediately spot a few savings, despite how horrible GAS syntax is to read...), but is definitely not "compiler slop"[1] either, which shows just how inefficient the majority of programs actually are. Of course even the ELF header takes up a significant amount of space, but this reminds me of how PC magazines would print short listings of utilities like this, often a few dozen up to a few hundred bytes at most --- in DOS .COM format, which is headerless and thus pure machine instructions.

[1] In the late 80s and early 90s, the battle between those writing handwritten Asm and those using compiled HLLs has many similarities to AI-generated vs non-AI code today.

bregma
As always with these admirable hacks, I feel compelled to point out these are not really ELF executables but just small files you can trick the x86_64 Linux kernel into loading.

I mean they're very clever and legit and kudos to the people who develop these exploits, but they're not ELF.

anonymous67453
Dell 5440

    $ git clone https://github.com/meribold/btry
    ...
    $ make
    as -mx86-used-note=no btry.s -o btry.o
    objcopy -O binary btry.o btry
    chmod +x btry

    $ ./btry 
    Segmentation fault         ./btry

    $ strace -f ./btry 
    execve("./btry", ["./btry"], 0x7ffc1a562078 /* 57 vars */) = -1 ENOMEM (Cannot allocate memory)

    $ file btry
    btry: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), statically linked, corrupted section header size
meribold
I fixed the most likely culprit now (excessively large p_memsz value). It cost a few bytes; the new executable size is 307 bytes.
bArray
I had a similar problem for a Thinkpad, except there is more than one cell at different capacities that are switched between. The existing battery manager would not tell me which battery was actually being used, and whether there was still a secondary battery waiting to be discharged.

I wrote a very quick hacky program for X11 that stays always visible that will display the information for any number of batteries: https://gitlab.com/danbarry16/bat_mon

It ends up being 50kB with minimal optimization and sports a lightweight X11 library (GUI) and JSON parser (configuration).