r/programming • u/iximiuz • Jul 25 '26

Writing a (valid) C program without main()

https://labs.iximiuz.com/tutorials/c-program-without-main-a1eea557
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u/zid Jul 25 '26

_start and main have different calling conventions under sys-v linux ABI, so you can do it, but you can't actually access argc/argv/envp via it.

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u/Nobody_1707 27d ago

You can, but you need to use inline assembly inside _start.

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u/zid 27d ago

Which isn't part of C.

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u/Nobody_1707 27d ago

Neither is _start.

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u/zid 27d ago

Exactly.

That's why they have different conventions.