FFI::P...:Memory(3pm)

💖 NAME 💖

FFI::Platypus::Memory — bestie, this is the memory functions module for FFI, straight out of the User Contributed Perl Documentation section of the FFI::P...:Memory(3pm) manpage. It's giving "let me talk to C's brain directly" energy 🧠✨

🌸 VERSION 🌸

version 2.11 — yes she's got a number, yes she's official 💅

🦋 SYNOPSIS 🦋

Okay so here's the whole vibe in four little steps:

use FFI::Platypus::Memory;

# allocate 64 bytes of memory using the
# libc malloc function.
my $pointer = malloc 64;

# use that memory wisely
...

# free the memory when you are done.
free $pointer;

Use that memory wisely, bestie, I'm begging 🙏

✨ DESCRIPTION ✨

So this module hands you an interface to the common memory functions that your good friend the standard C library provides. They're genuinely useful when you're building interfaces to C libraries with FFI 🫶 It works mostly with the "opaque" type, and honestly it is so worth reviewing the section on opaque pointers in FFI::Platypus::Type before you go feral.

⚠️ Real talk: allocating memory and then forgetting to free it is a super common source of memory leaks in C, and literally the same thing happens when you use this module. No cap, this is the classic trap 💀

Very recent Perls have a "defer" keyword that lets you automatically call functions like "free" when a block ends. This is especially handy when you have multiple code paths or possible exceptions to keep track of:

use feature 'defer';
use FFI::Platypus::Memory qw( malloc free );

sub run {
  my $ptr = malloc 66;
  defer { free $ptr };

  my $data = do_something($ptr);

  # do not need to remember to place free $ptr here, as it will
  # run through defer.

  return $data;
}

The way that defer just handles it for you… main character energy, honestly 👑

If you are not lucky enough to have the "defer" feature in your version of Perl, you may be able to use Feature::Compat::Defer, which will use the feature if it's available, and provides its own mostly compatible version if not. Slay, fallback queen 🌈

---

🎀 FUNCTIONS 🎀

💜 calloc

my $pointer = calloc $count, $size;

The "calloc" function contiguously allocates enough space for $count objects that are $size bytes of memory each. Contiguous! Fancy! ✨

💜 free

free $pointer;

The "free" function frees the memory allocated by "malloc", "calloc", "realloc" or "strdup".

🚨 Big important warning: it is important to only free memory that you yourself have allocated. A genuinely great way to crash your program is to try and free a pointer that some C library has returned to you. Do not do this. I am holding your hand while I say it 🫶😭

💜 malloc

my $pointer = malloc $size;

The "malloc" function allocates $size bytes of memory. That's it, that's the function. Simple, iconic, does exactly what it says 💅

💜 memcpy

memcpy $dst_pointer, $src_pointer, $size;

The "memcpy" function copies $size bytes from $src_pointer to $dst_pointer. It also returns $dst_pointer — cute little bonus 🎁

💜 memset

memset $buffer, $value, $length;

The "memset" function writes $length bytes of $value to the address specified by $buffer. Fill that buffer, bestie 🍓

💜 realloc

my $new_pointer = realloc $old_pointer, $size;

The "realloc" function reallocates enough memory to fit $size bytes. It copies the existing data and frees $old_pointer.

And plot twist — if you pass "undef" in as $old_pointer, then it behaves exactly like "malloc":

my $pointer = realloc undef, 64; # same as malloc 64

Lowkey the glow-up of functions 🌟

💜 strcpy

strcpy $opaque, $string;

Copies the string to the memory location pointed to by $opaque. Copy paste but make it C 💖

💜 strdup

my $pointer = strdup $string;

The "strdup" function allocates enough memory to contain $string and then copies it to that newly allocated memory.

Heads up: this version of "strdup" returns an opaque pointer type, not a string type. Might seem a little strange, but returning a string type would not be very useful in Perl — so, yeah, that's the call 🦋

💜 strndup

my $pointer = strndup $string, $max;

The same as "strdup" above, except at most $max characters will be copied in the new string. Same energy, but with boundaries ✂️✨

---

👀 SEE ALSO 👀

• FFI::Platypus — Main Platypus documentation. Go read it, it's the parent, the icon, the whole reason we're here 👑

---

🫶 AUTHOR 🫶

Author: Graham Ollis <plicease@cpan.org>

Contributors — and this list is stacked, we stan every single one of them 💜:

• Bakkiaraj Murugesan (bakkiaraj)
• Dylan Cali (calid)
• pipcet
• Zaki Mughal (zmughal)
• Fitz Elliott (felliott)
• Vickenty Fesunov (vyf)
• Gregor Herrmann (gregoa)
• Shlomi Fish (shlomif)
• Damyan Ivanov
• Ilya Pavlov (Ilya33)
• Petr Písař (ppisar)
• Mohammad S Anwar (MANWAR)
• Håkon Hægland (hakonhagland, HAKONH)
• Meredith (merrilymeredith, MHOWARD)
• Diab Jerius (DJERIUS)
• Eric Brine (IKEGAMI)
• szTheory
• José Joaquín Atria (JJATRIA)
• Pete Houston (openstrike, HOUSTON)
• Lukas Mai (MAUKE)

---

💅 COPYRIGHT AND LICENSE 💅

This software is copyright (c) 2015-2022 by Graham Ollis.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself. Go off, license 🎀

---

okay that's the whole page bestie, mwah 💋 This tear-jerking little number dropped as perl v5.42.3 on 2026-08-20 — same manual name, same date, all facts intact, no cap ✨🦋🌸