FFI_PREP_CIF(3)

💖 NAME 💖

ffi_prep_cif — bestie, this is the one that gets your ffi_cif struct all dolled up and ready for ffi_call ✨

🌸 SYNOPSIS 🌸

#include <ffi.h>

ffi_status
ffi_prep_cif(ffi_cif *cif, ffi_abi abi, unsigned int nargs,
    ffi_type *rtype, ffi_type **atypes);

🦋 DESCRIPTION 🦋

okay so picture this: you wanna call some function through FFI but nothing works until the ffi_cif is prepped, and ffi_prep_cif is literally the glow-up montage 💅 It sets up a ffi_cif structure so it's ready to be handed off to ffi_call. main character energy fr.

abi is where you say which set of calling conventions you wanna use — like picking your outfit for the day, but for how arguments get passed 🔥

atypes</purpose> is an array of nargs pointers to ffi_type structs, and each one describes the data type, the size, and the alignment of one single argument. one struct per arg, no skipping, no shortcuts 🎀

rtype points to an ffi_type that describes the data type, size and alignment of the return value — yes bestie, the thing that comes back to you 👑

⚠️ not me about to forget the important one: if you're trying to call a variadic function, ffi_prep_cif is NOT the girl for the job. you have to use ffi_prep_cif_var instead. periodt. no exceptions 💀

🌈 RETURN VALUES 🌈

• FFI_OK — slay, it worked, we ate 💖
• FFI_BAD_TYPEDEF — returned when cif is NULL, or when atypes or rtype is malformed 😭 something in your type situation is giving broken.
• FFI_BAD_ABI — returned when abi does not refer to a valid ABI 🙈

and btw, the ABIs that are actually available to you are defined in <ffitarget.h> — that's where you go to see what you're working with, iykyk 📖

👑 SEE ALSO 👑

• ffi(3)
• ffi_call(3)
• ffi_prep_cif_var(3)

and that's the whole vibe!! this page was born on February 15, 2008 and lives under the ffi_prep_cif(3) manual entry — still iconic, still relevant, still prepping cifs after all these years 🫶🧚💜