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Comment by Alupis | Hacker News Reader

I'm not sure I understand how it's "self replicating"? An empty file, compiled or not, won't replicate itself. The Makefile to compile the empty c file is also rather large, but even it must be executed in a loop.

Can someone explain the basis of this contest and how this c file is "self-replicating"?

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It's abuse of the contest rules, which encouraged at the IOCCC. You just have to be absolutely certain that it really IS "technically valid"[1] or it risks disqualification.

This one abuses the idea that they specify how the contest will be judged, which this "program" satisfies, as long as you don't look at the source.

    $ make smr
    cp smr.c smr
    chmod +x smr
    $ ./smr > smr.dup
    $ diff smr smr.dup
    $ echo $?
    0

Also, it is a valid C file!

    $ stat -c "%s" smr.c
    0
    $ gcc -Wall -c smr.c
    $ echo $?
    0
    $ stat -c "%s" smr.o
    927

The judge's comments for this one explain this in a bit more detail:

http://www.ioccc.org/1994/smr.hint

[1] the best kind of "valid" :)

If you also look into the Makefile accompanied, it's just copying itself to smr file and giving it executable rights. So smr.c when built outputs it's source code.

The makefile is not large. It's a makefile for all the entries for 1994 competition. And it's only 4 lines for smr.c

I think what they were referring to was a quine

yes, but is using an external program (make and cp) really count? I wouldn't consider that really as "self-replicating".

every self replicating entry in the competition is compiled with other binaries.

And most of biology (including you).

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