> For the complete documentation index, see [llms.txt](https://docs.gamesense.biz/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.gamesense.biz/pt-br/api-reference/ffi.md).

# FFI

Leitura e gravação de buffers binários tipados.

O módulo `ffi` integrado fornece buffers tipados para leitura e gravação de dados binários.

O módulo é carregado com `require("ffi")`.

## ffi.buffer

`ffi.buffer(size: integer): ffi_buffer`

Aloca um buffer de `size` bytes.

```lua
local ffi = require("ffi")
local data = ffi.buffer(8)

data:set_u32(0, 256)
local value = data:get_u32(0)
```

## ffi\_buffer:size

`buffer:size(): integer`

Retorna o tamanho do buffer em bytes.

## Leitura e gravação

Métodos `get_*` leem valores; métodos `set_*` gravam valores. Os deslocamentos são **posições em bytes, começando em zero**.

| Tipo   | Leitura            | Gravação                  |
| ------ | ------------------ | ------------------------- |
| UInt8  | `:get_u8(offset)`  | `:set_u8(offset, value)`  |
| Int8   | `:get_i8(offset)`  | `:set_i8(offset, value)`  |
| UInt16 | `:get_u16(offset)` | `:set_u16(offset, value)` |
| Int16  | `:get_i16(offset)` | `:set_i16(offset, value)` |
| UInt32 | `:get_u32(offset)` | `:set_u32(offset, value)` |
| Int32  | `:get_i32(offset)` | `:set_i32(offset, value)` |
| Int64  | `:get_i64(offset)` | `:set_i64(offset, value)` |
| Float  | `:get_f32(offset)` | `:set_f32(offset, value)` |
| Double | `:get_f64(offset)` | `:set_f64(offset, value)` |

```lua
local buffer = require("ffi").buffer(8)
buffer:set_i32(0, -50)
buffer:set_f32(4, 1.25)

local count = buffer:get_i32(0)
local multiplier = buffer:get_f32(4)
```

Acessos fora dos limites do buffer causam erros. O tamanho máximo padrão de um buffer é **1 MiB**.

{% hint style="warning" %}
Esta é uma implementação FFI integrada e restrita, **não o LuaJIT FFI**. Funções como `ffi.cdef` e `ffi.cast` não estão disponíveis.
{% endhint %}


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