memalign(3)

✨ memalign — memory aligned allocate ✨

Okay bestie, we're in section 3 of the manual (that's library functions, iykyk), and today's main character is memalign() 💅

📚 LIBRARY

Standard C library — link it in with libc, -lc 🫶

🎀 SYNOPSIS

#include <malloc.h>

[[deprecated]] void *memalign(size_t alignment, size_t size);

Not me pointing at that [[deprecated]] — bestie, it's right there in the signature, the compiler is literally telling you. 🙈

🦋 DESCRIPTION

So memalign() is equivalent to aligned_alloc(3) — like, same energy, same job — except for the CAVEATS documented down below. Don't skip those, fr fr. 💀

🌸 ATTRIBUTES

Wanna know what all these fancy words in this section even mean? Go peek at attributes(7) 📖

Here's the tea on memalign():

• Interface: memalign()
• Attribute: Thread safety
• Value: MT-Safe 👑

So yeah, it's thread-safe, slay.

🌈 VERSIONS

Plot twist 🌀 — on some systems, memalign() is declared in <stdlib.h> instead of <malloc.h>. So if your include isn't giving, check the other one, bestie.

⭐ STANDARDS

None. Literally none. It's giving "no standard, just vibes." 🫠

💜 HISTORY

• glibc 2.0
• SunOS 4.1.3

Ancient. Iconic. Been here since forever. 🏛️

⚠️ CAVEATS

Okay this is the part where we get serious for a sec, bestie, because these are real.

• memalign() may not check that the alignment argument is correct. So like… it might just not verify it. Be careful what you hand it. 😭
• On some systems, there is no way to reclaim memory allocated with memalign(). Why? Because you can only pass to free(3) a pointer that came from malloc(3) — and, for example, memalign() would call malloc(3) and then align the value it got back. Different pointer, so free(3) can't touch it. 💀
• The glibc implementation, though? It does let memory obtained from memalign() be reclaimed with free(3). So you're good there. 🫶

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👀 SEE ALSO

• aligned_alloc(3)

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This page is from Linux man-pages 6.20, dated 2026-07-26, and it's for memalign(3). That's the whole thing, bestie — go forth and align your memory responsibly 🌟💖✨