fix: add suffix

Signed-off-by: Paolo Insogna <paolo@cowtech.it>

Author: ShogunPanda

doc/api/ffi.md

@@ -137,6 +137,28 @@ const signature = {
 };
 ```
 
+## `ffi.suffix`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+* {string}
+
+The native shared library suffix for the current platform:
+
+* `'dylib'` on macOS
+* `'so'` on Unix-like platforms
+* `'dll'` on Windows
+
+This can be used to build portable library paths:
+
+```cjs
+const { suffix } = require('node:ffi');
+
+const path = `libsqlite3.${suffix}`;
+```
+
 ## `ffi.dlopen(path[, definitions])`
 
 <!-- YAML

lib/ffi.js

@@ -17,7 +17,6 @@ const {
   validateInteger,
   validateString,
 } = require('internal/validators');
-const { __proto__ } = require('console');
 
 emitExperimentalWarning('FFI');
 
@@ -132,6 +131,8 @@ function exportBuffer(buffer, data, len) {
   buffer.copy(targetBuffer, 0, 0, buffer.length);
 }
 
+const suffix = process.platform === 'win32' ? 'dll' : process.platform === 'darwin' ? 'dylib' : 'so';
+
 const types = ObjectFreeze({
   __proto__: null,
   VOID: 'void',
@@ -184,6 +185,7 @@ module.exports = {
   setUint64,
   setFloat32,
   setFloat64,
+  suffix,
   toString,
   toArrayBuffer,
   toBuffer,